If we had research paths like astrophysics or Metallurgy or Materials Sciences, Computer Technology, Nanophysics etc etc etc I'd enjoy the immersion.
I think Space Empire (IV at least) had something like that where you splitted a percentage of your research pool in different research fields. I really liked it and it was a lot of fun discovering what kind of new technology you could get for your ships or planets. Eventually, after playing games a couple of times you'd kind of know which path (and combination of paths) would yield the supper cool tech, but for the first few play through there was a lot of exploration and wonder from it. I liked for example that you could eventually get some powerful and usefull tech from investing a lot in fundamental physics, which would not give you much of anything until you invested a lot in it.
Maybe my memory is a bit fussy on the details, but in summary what I really liked is the concept of "exploring" the research paths/trees and the payoff with meaningful tech you'd get from it.
