I realize that this has been discussed before by people, but whenever I have looked at these boards there is never a major topic about it, so I just wanted to give my opinion on this subject. It may be a little lengthy, so grant me a little patience.
Frankly, I think that the tech tree is by far the weakest part of Galactic Civilizations II. It is bland, uninteresting, extremely linear, and the weapon tech treess are unnecessarily large. I really do not understand the logic behind creating lasers 1-5, etc, for all of the different weapon technologies, especially when each subsequent advance is almost completely useless. What purpose could gaining a tech that is 1 smaller in size possibly have?
This is a flaw which is experienced in the other branches as well, but to a lesser degree. I just can't help thinking while playing, "Oh yay, now I have Xeno Farming II instead of Xeno Farming I, what a great breakthrough." Like many people, I judge this game by the standard set by MoO2, and that game, although almost 10 years old now, has an infinetely more interesting and engaging tech tree.
Where are all the unexpected techs, the ones you get that give you some special ability or building that is no where else available on the tech tree? Quite frankly, there are NO techs which give you uniquie buildings (save achievements, projects, and trade goods), whereas in MoO2, EVERY new tech gave you distnct and new buildings, not just upgrades of previous buildings. I realize that because space is limited on each planet in this game, that this has to be done to a very high degree, but I think that there is still a lot of room for unique techs and buildings which don't fit neatly into the linear tech tree Stardock has created.
Again concerning the tech tree, I definitely think that there should be more options as far as terraforming is concerned. If you are willing to invest enough research, and then social production to try and continue to terraform a planet you should be able to do so. I think that the highest tech in terraforming should allow you to make all land (not ocean) on the planet habitable, with the social production cost increasing for each subsequent terraforming operation. I think this works much better than forcing the player to be stuck with a Class 5 planet which is clearly so huge it should be able to support a much higher amount of buildings.
Furthermore on this note, I agree with other people who have said it should be possible to colonize/terraform or at least explore class 0 worlds. This relatively minor addition would add a whole new aspect to the game altogether.
The reason I'm making this post is not because I think Stardock will jump up and decide to revamp their entire tech tree over it, but because I think that they should know everyone is not happy with the way they have implemented it. What concerns me the most is reading posts from Frogboy saying how the tech tree is a minor thing to him, something that should occur in the background and that the player shouldn't have to be concerned with. This is a science fiction game, and technology is the cornerstone of science fiction, no matter how you look at it.
People who play science fiction games want an interesting and intriguing tech tree which makes it feel like they are actually researching new things, not just getting a new bonus to some gameplay mechanic.