"One thing I haven't seen much in any game is for each race to have slightly different tech trees and techniques- for instance, one of the races I am working on for my sci-fi game has basically the exact same Traveller technologies as they are listed in the books, but all their equipment is based on a crystal matrix, with the handwave being "crystalline circuits" being created with special "forges" and psi masters- a variation of the Sohon techniques used with nanites in the Legacy of the Aldenata series. It really makes the setting a bit more realistic to me when separate peoples discovers how the universe works in different ways. A tad more complicated I grant you, but very satisfying. With the benefit that players can't always just drop that alien tech into a slot and make it work. Mean of me, but thats my job..."
Breaking this off into its own thread.
With Traveller you also are working under the assumption that the vast majority of the tech encountered is Imperial and thus human. Then again, the Zhodani have different tech in how it is utilized, though it is often comparable to Imperial tech.
I think in the "core" rules there really should be a single overarching tech tree. You can then work the techs of the "races" from it, handwaving however you want the "basis" for the tech. Do keep in mind though if you start basing your tech off of something other than what we know of science, you begin diverging into science-fantasy. Not that that is always a bad thing, but it is something to keep in mind. It's not like there aren't already handwaves throughout, but the more you add and the more based on the imagination you get...




Don't get me wrong, I'm with you on using alternate tech bases for an alien race, it definitely helps make them more alien. But as a game designer I've also got to try and keep things as reasonably simple as possible for gaming purposes. So going with a separate tech base for every race is problematic, but not so much if you instead choose one race to be the really different one. Much like the Vhong(?) in the Star Wars books. Bruce and I have toyed with an alien race that has it's tech basis in biogenetics, but trying to put a spin on it that hasn't already been done and at the same time keep it playable. Not necessarily an easy task.
I do like the idea of some races having an "edge" in certain technological areas as you mentioned. That is something that can be easily quantified into game mechanics and also helps differentiate races from one another.