I was very happy when I seen some of my suggestions in dark avatar I been busy and failed to give more suggestions to the developers! I hope they see this! anyway first of all the idea of completely different tech trees is good, and it reminded me of something very cool there is in a very old 4x strategy game called "birth of the federation"
the minor races there did play an IMPORTANT role so important that annexing them to your empire let you get ahold of their special tecnology (basically a galactic wonder that gives empire-wide bonuses) since all techs are unique for major races would you do something nice for minor races? like they each have 1 unique galactic wonder each and you gotta conquer/annex them peacefully to get it? back in birth of federation some gave empire wide morale other empire wide reistance to birbery others empire-wide bonus to the research factor of a certain tech (like +25% in bio-engineering field of science) since we got fields of science (red, yellow, green, blue etcetera) those kind of bonuses could be possible at all?
of course back in birth of the federation the minor races was really really alot and here we got like 8 or so (can't remember exactly) what you think of the idea? could it be possible?

also I'm very interested in the unique tech trees and the planet annexation facilities, would you be able to learn the 'dregin way of do stuff' from the facilities and decide or not to apply it?