This is not a trick question. At this point in time, ground combat is probably the weakest part of the game. So let's try to being together some ideas on how it could be improved.
First, the problems:
1. Mousecklicks. Building armies, clicking on each one individually to give them attachments (most of which are quite similar) is way too much pointless clicks. Attachments need to either be removed, or turned into something more meaningful. A "auto-attach" or some other QoL option would help too to reduce clicks, as well as sectors automatically building the "neo-concrete" attachments for their defensive armies to reduce maintenance.
2. Lack of defensive options. There really is nothing. Fleet shows up, bombs, dumps troops. If your troops have a bigger numbers, you win. Army recovers and can move to next target. There is literally nothing else. There is no difference between invading a desert world, some tropical world filled with hallucinogens and vicious wildlife, a world with titanic lifeforms or with underground cave aliens. There is so much variety in the planets, and it's not used at all.
3. Lack of troop variety. There is no real variety, you have one troop class: the attack one with straight up superior versions appearing later on. Garrisons become irrelevant by mid-game. Defensive armies become irrelevant a little later. This results in no real army planning other than "build stack of identical units".
Why do we want good ground combat? Because it can be very fun! The best 4x I have played with ground combat is MOO3, which unfortunately was plagued the whole game's "interface from hell" problem. Neverthless, it has been years, but I still remember:
I was playing as Humans (who are totally terrible in ground combat), and was fighting Meklar (who are quite decent). Victory in space was achieved, but to progress further, I needed to actually take the planets. And that's where problems started. The Meklar fortified every major world with lots of armies. Since these worlds were well delopped I wanted them relatively intact so bombing them to extinction was not an option. Additionally, combat stance had to be set to "low collateral damage". That, combined with the humans' poor combat ability made conquest difficult. My armies got stuck in attritional warfare, where I was slowly edging the planet one region at a time. One planetary invasion failed to land and was destroyed, another did not receive reinforcements in time and was overrun.
I needed to actually plan carefully for the ground war. I went and traded techs to get better defensive equipment for my troops. I had to cancel production on worlds which had non-human population and focus them on producing only troops (since they were better). I had to organise new model armies (MOO3 had a neat army designer from small units, with different troop classes) with more more frontline troops and less support (as my armies already on planets still had their support, but were running out of actual grunts. I had to put a new generation of transport ships into production to get my troops to the fight in less turns.
So, this was fun, it was, well, strategic. And it was so so rewarding to watch the very MOO3-ugly interface turning the planet map into my color as I was sweeping the enemy troops.
First, the problems:
1. Mousecklicks. Building armies, clicking on each one individually to give them attachments (most of which are quite similar) is way too much pointless clicks. Attachments need to either be removed, or turned into something more meaningful. A "auto-attach" or some other QoL option would help too to reduce clicks, as well as sectors automatically building the "neo-concrete" attachments for their defensive armies to reduce maintenance.
2. Lack of defensive options. There really is nothing. Fleet shows up, bombs, dumps troops. If your troops have a bigger numbers, you win. Army recovers and can move to next target. There is literally nothing else. There is no difference between invading a desert world, some tropical world filled with hallucinogens and vicious wildlife, a world with titanic lifeforms or with underground cave aliens. There is so much variety in the planets, and it's not used at all.
3. Lack of troop variety. There is no real variety, you have one troop class: the attack one with straight up superior versions appearing later on. Garrisons become irrelevant by mid-game. Defensive armies become irrelevant a little later. This results in no real army planning other than "build stack of identical units".
Why do we want good ground combat? Because it can be very fun! The best 4x I have played with ground combat is MOO3, which unfortunately was plagued the whole game's "interface from hell" problem. Neverthless, it has been years, but I still remember:
I was playing as Humans (who are totally terrible in ground combat), and was fighting Meklar (who are quite decent). Victory in space was achieved, but to progress further, I needed to actually take the planets. And that's where problems started. The Meklar fortified every major world with lots of armies. Since these worlds were well delopped I wanted them relatively intact so bombing them to extinction was not an option. Additionally, combat stance had to be set to "low collateral damage". That, combined with the humans' poor combat ability made conquest difficult. My armies got stuck in attritional warfare, where I was slowly edging the planet one region at a time. One planetary invasion failed to land and was destroyed, another did not receive reinforcements in time and was overrun.
I needed to actually plan carefully for the ground war. I went and traded techs to get better defensive equipment for my troops. I had to cancel production on worlds which had non-human population and focus them on producing only troops (since they were better). I had to organise new model armies (MOO3 had a neat army designer from small units, with different troop classes) with more more frontline troops and less support (as my armies already on planets still had their support, but were running out of actual grunts. I had to put a new generation of transport ships into production to get my troops to the fight in less turns.
So, this was fun, it was, well, strategic. And it was so so rewarding to watch the very MOO3-ugly interface turning the planet map into my color as I was sweeping the enemy troops.