I've been trying to split out various aspects of needed corrections for missiles and strike craft (see the first few linked threads/posts in my signature), to better focus discussions on each topic, rather than getting lost in the enormity of the problem by taking it all at once. This next discussion is centered on the flight speed for missiles and strike craft.
There are currently three classes of weapon speed in Stellaris: (near) instantaneous, very fast, and deathly slow. Beam weapons and some kinetics fire and apply their effects within 0-2 days (only limited by range), while nearly all other energy and kinetic weapons will hit their targets within 2-5 days of firing at range. And then we get to missiles, where a max range shot for an L-slot weapon takes 18 days to travel from launcher to target.
The problem with that system is that the equations for targeting do a poor job of accounting for in-flight attacks in determining whether to send additional ordinance downrange. Given the cooldown rates of the different weapons, only those kinetic and energy weapons (anywhere from 2.35 to 4.35 days) with both the slowest projectiles and the longest ranges will see same-launcher overkill due to a projectile still being in-flight when the next volley's target is calculated. But a missile system, like the L-slot weapon above, could easily have as many as three projectiles in-flight when it calculates yet another launch. Again, this is just same-launcher overkill - missiles that are in-flight can easily be rendered moot due to kinetic/energy attacks being made without regard to the already incoming projectiles.
All of this is based on the vanilla missile speed of 5 distance units per day. What would really be the difference in increasing the speed on missiles? An S-slot missile mount fires at its max range of 50 and with the speed at 5 and the cooldown at 5.5 days, a second potentially-overkill salvo is almost guaranteed. Bump the speed up to 10, and the S-slot never self-overkills. The M-slot missile goes from 2 self-overkills to just 1, and the L-slot from 3 to 1. That's only increasing speed by a factor of 2 (or +100%) - greater speed increases might improve this more, although at least one thread I've read talked about some weird behavior for missiles beyond speeds of 15 or 20.
What else happens? A target that is killed days earlier (because the fatal shots got there quicker) isn't able to fire back for a longer period. While I've already recommended neutering PD to a short enough range that the same PD mount wouldn't be able to fire multiple shots (larger PD slots would have a high enough RoF, but that would still be limited), flak weapons even with their range would get fewer passing shots on the same missile if it moves through the area quicker.
Will there still be overkill more often with missiles involved than without? Yes, unless Paradox does something with the actual targeting equations to include in-flight projectiles, and even then PD/flak or variable damage may force a safety margin of potential damage that might be wasted, but hopefully that would be similar to kinetic/energy accuracy being prone to RNG weirdness.
Now we get to strike craft, where the consideration is based on engagement distance versus effective range for other weapons. By this I mean a strike craft (i.e., bomber) squadron that launches takes time to get into weapons range of their targets. If the bombers' speed is 5 and they have to get within a distance of 8 to start firing, they would need 22.5 days to travel from a launch distance of 120 to get in range (assuming no movement by the target). (I'm not certain of actual combat speed for the main warships, but I'm running with the Max Speeds shown in the Wiki of 1.75 for Corvettes, 1.25 for Destroyers and Cruisers, and 0.75 for Battleships, in order to determine where the launching fleet would be when the squadron is in range.)
A Cruiser (or a Destroyer, if you agree to my proposal linked below) would move up all of about 30 units in that time, which would allow some L-slot weapons to start firing right about when the bombers do. A Battleship would either get enough for a 110 shot or a few days from firing 100-distance Kinetic Artillery. Looking at those numbers, it almost seems like strike craft don't need a speed boost. But if we allow the targeted fleet to close the distance, too, then enemy Corvettes get close enough for many M-slot weapons, and the bigger ships would face fire from most to nearly all L-slot weapons, all before the bombers can get off a single shot. I would recommend changing the starting base speed for strike craft to either 7 or 8 (they shouldn't be as fast as missiles, because IRL missiles wouldn't need to accelerate away from their launcher, decelerate to match speed on target, loiter while changing vectors, accelerate back to their carrier, and decelerate to land, so they could just dump all their fuel in one go).
However, those distances and speeds assume that only the default technologies are being used - new thrusters can make warships faster, but there currently aren't any increases offered for missile or strike craft flight speed. As the higher level missile and strike craft technologies don't have thruster technologies as prerequisites, I would offer a small but increasing bonus to flight speeds for all researched missiles and strike craft when completing research on thruster techs, and then higher base speeds (again small increases) for each tier of basic missile or strike craft tech. For example, the new Tier 1 missile's base flight speed could be 10 units, which goes up to 11/12/13/14 as you go up in Tier, while Ion Thrusters would add a separate +5% modifier to flight speed, going up to +10% for Plasma and +15% for Impulse. So net, a Tier 3 missile alongside Plasma Thrusters would have a flight speed of about 13.2, while a Tier 5 with Impulse would be 16.1 units. Strike craft would probably be in a similar situation, with base flight speeds 7/9/11 or 8/10/12 and the same percentile boosts for Thruster techs.
Off-topic for a moment: I've seen other games have a similar technology, but could you have a "missile" tech that has one of the Jump Drives as a prerequisite, where a device micro-jumps across to the enemy fleet, past any PD/flak/CAP (Combat Air Patrol, fighter screen), and detonates a larger warhead (the device is basically all warhead) right on the target? Perhaps make that (one of) the XL weapon that missiles have been missing...
Again, all of this discussion here is just a piece of the larger group of concerns about missiles and strike craft. Please read and if you wish contribute to this and the other threads linked in my signature, but try to focus on flight speed issues in this thread. Thanks for reading!
There are currently three classes of weapon speed in Stellaris: (near) instantaneous, very fast, and deathly slow. Beam weapons and some kinetics fire and apply their effects within 0-2 days (only limited by range), while nearly all other energy and kinetic weapons will hit their targets within 2-5 days of firing at range. And then we get to missiles, where a max range shot for an L-slot weapon takes 18 days to travel from launcher to target.
The problem with that system is that the equations for targeting do a poor job of accounting for in-flight attacks in determining whether to send additional ordinance downrange. Given the cooldown rates of the different weapons, only those kinetic and energy weapons (anywhere from 2.35 to 4.35 days) with both the slowest projectiles and the longest ranges will see same-launcher overkill due to a projectile still being in-flight when the next volley's target is calculated. But a missile system, like the L-slot weapon above, could easily have as many as three projectiles in-flight when it calculates yet another launch. Again, this is just same-launcher overkill - missiles that are in-flight can easily be rendered moot due to kinetic/energy attacks being made without regard to the already incoming projectiles.
All of this is based on the vanilla missile speed of 5 distance units per day. What would really be the difference in increasing the speed on missiles? An S-slot missile mount fires at its max range of 50 and with the speed at 5 and the cooldown at 5.5 days, a second potentially-overkill salvo is almost guaranteed. Bump the speed up to 10, and the S-slot never self-overkills. The M-slot missile goes from 2 self-overkills to just 1, and the L-slot from 3 to 1. That's only increasing speed by a factor of 2 (or +100%) - greater speed increases might improve this more, although at least one thread I've read talked about some weird behavior for missiles beyond speeds of 15 or 20.
What else happens? A target that is killed days earlier (because the fatal shots got there quicker) isn't able to fire back for a longer period. While I've already recommended neutering PD to a short enough range that the same PD mount wouldn't be able to fire multiple shots (larger PD slots would have a high enough RoF, but that would still be limited), flak weapons even with their range would get fewer passing shots on the same missile if it moves through the area quicker.
Will there still be overkill more often with missiles involved than without? Yes, unless Paradox does something with the actual targeting equations to include in-flight projectiles, and even then PD/flak or variable damage may force a safety margin of potential damage that might be wasted, but hopefully that would be similar to kinetic/energy accuracy being prone to RNG weirdness.
Now we get to strike craft, where the consideration is based on engagement distance versus effective range for other weapons. By this I mean a strike craft (i.e., bomber) squadron that launches takes time to get into weapons range of their targets. If the bombers' speed is 5 and they have to get within a distance of 8 to start firing, they would need 22.5 days to travel from a launch distance of 120 to get in range (assuming no movement by the target). (I'm not certain of actual combat speed for the main warships, but I'm running with the Max Speeds shown in the Wiki of 1.75 for Corvettes, 1.25 for Destroyers and Cruisers, and 0.75 for Battleships, in order to determine where the launching fleet would be when the squadron is in range.)
A Cruiser (or a Destroyer, if you agree to my proposal linked below) would move up all of about 30 units in that time, which would allow some L-slot weapons to start firing right about when the bombers do. A Battleship would either get enough for a 110 shot or a few days from firing 100-distance Kinetic Artillery. Looking at those numbers, it almost seems like strike craft don't need a speed boost. But if we allow the targeted fleet to close the distance, too, then enemy Corvettes get close enough for many M-slot weapons, and the bigger ships would face fire from most to nearly all L-slot weapons, all before the bombers can get off a single shot. I would recommend changing the starting base speed for strike craft to either 7 or 8 (they shouldn't be as fast as missiles, because IRL missiles wouldn't need to accelerate away from their launcher, decelerate to match speed on target, loiter while changing vectors, accelerate back to their carrier, and decelerate to land, so they could just dump all their fuel in one go).
However, those distances and speeds assume that only the default technologies are being used - new thrusters can make warships faster, but there currently aren't any increases offered for missile or strike craft flight speed. As the higher level missile and strike craft technologies don't have thruster technologies as prerequisites, I would offer a small but increasing bonus to flight speeds for all researched missiles and strike craft when completing research on thruster techs, and then higher base speeds (again small increases) for each tier of basic missile or strike craft tech. For example, the new Tier 1 missile's base flight speed could be 10 units, which goes up to 11/12/13/14 as you go up in Tier, while Ion Thrusters would add a separate +5% modifier to flight speed, going up to +10% for Plasma and +15% for Impulse. So net, a Tier 3 missile alongside Plasma Thrusters would have a flight speed of about 13.2, while a Tier 5 with Impulse would be 16.1 units. Strike craft would probably be in a similar situation, with base flight speeds 7/9/11 or 8/10/12 and the same percentile boosts for Thruster techs.
Off-topic for a moment: I've seen other games have a similar technology, but could you have a "missile" tech that has one of the Jump Drives as a prerequisite, where a device micro-jumps across to the enemy fleet, past any PD/flak/CAP (Combat Air Patrol, fighter screen), and detonates a larger warhead (the device is basically all warhead) right on the target? Perhaps make that (one of) the XL weapon that missiles have been missing...
Again, all of this discussion here is just a piece of the larger group of concerns about missiles and strike craft. Please read and if you wish contribute to this and the other threads linked in my signature, but try to focus on flight speed issues in this thread. Thanks for reading!
