[Neferti]

I agree with Wakey (he's stated this elsewhere...). I don't think it should be possible to finish all the research. If you can't complete the tech tree 100% then it adds more decision making to your round. Do you go for big ships, or scans, or what?

Branching might be nice too. We had a (sort of) branching tech tree back in rounds 4 and 5, where you had to decide between 'kill' and 'science' (something like that). 'Kill' was pretty much equivalent to Terran now. Science had Cathaar and Xandrathii elements (EMP and cloaked ships). Obviously that became obsolete with the introduction of races, but I'm sure some way could be found to do that again...