Turning off the Tech Tree in the average game is not something we've considered - the randomized tech tree does two very important things in the game; it eliminates the otherwise impossible to avoid Perfect Path To Game Dominance seen in other games with a static tree. And it removes racial tech weighting, which is part (not all, but a not inconsiderable part) of keeping the aliens races from being carbon copies of one another.
There are ways, like a specific scenario, that a player can try that kind of game (with the predictable "under these circumstances, particular races are unbalanced good/bad"), but it's something we have to be very careful about allowing in the core of the game. Hopefully that makes sense - I'm reading the boards on the run today!
If I might, I'll try to keep this concise. Though I can understand the desire to have random tech trees and, to a degree, I actually like said random tech trees, the system could certainly stand to have some tweaks.
As some examples. I found that, when playing a game, I would usually determine what type of weapon I wanted to use. For instance, mass drivers, energy (in general), projectors, missiles, some combination of these. Then I'd look at a research chart detailing percentages. If I wanted to go mass drivers, I almost exclusively went human/hiver/tarka. If I went Energy, I'd go morrigi or liir, without exception. In an effort to create randomness, the tree actually just heavily promoted me going specific races instead. This is okay from a stylistic standpoint, but I'd much rather not be forced into being a morrigi because I want to use beam weapons.
In addition to this, some techs just have to be guarantees in my opinion. For instance, economy and colonization techs should be guaranteed. If you're in a game where you happen to get arcology, that's a huge benefit to you. But, if you're in a game where your enemy got it and you didn't, you could very easily get economically overpowered through no fault of your own. Not because of inferior weapons, but because you just can't outproduce some of these techs.
Not getting Biome, as well, could cause massive issues with the mid-game where you're trying to expand and beat out the AI, as it really slows the entire game down. These are examples of techs that shouldn't be random. As an idea, it might be interesting to see race play a factor in how colonization and economy goes, instead of having unknown numbers that just dictate growth rates, the game could instead promote, for instance, the Morrigi trade-based economy, while humans might have a weird capitalistic economy with fluctuations, with hivers just being communal in nature...you get the idea.
In addition to this, it might be worth considering tech tree specializations. As I said earlier, I often played my game to where I made my choice based off of what weapons my race got. This is, again, not a good design of random, as you're guiding and promoting optimal choice based off of what is most likely, not what is most interesting.
It might be worth considering, then, to add some sort of specialization feature to the race, where you can, for instance, guarantee a large chunk, if not all of, the Mass Driver line of weapons (within reason). This could have the tradeoff of reduced chances to research plasma cannons or phasers or the like. Doesn't have to be a net gain, and it would help promote random over simply always specializing, but I digress. It still would allow for random in that, if you don't want to use AP, for instance, you'd still need to win a roll for fire control or AI fire control, but it would mean your late-game isn't completely devastated because your chosen path didn't have tungsten ammo.
I like everything you've covered so far, and I'd get SotS2 regardless, I just loved the original too much despite its flaws. It would just be nice to see a few of the kinks ironed out. The research tree being where some of the largest are.
