Good read. Funny thing is that I own almost every game mentioned in their original state. I have like three copies of Master of Orion, including the release that came on floppies and had copy-protection of asking you names of starships (which you could only get from the manual (which of course I saved!)).
Anyway, I miss LGS for Terra Nova: Strike Force Centauri almost as much as I miss them for System Shock and Thief. TN:SFC was another great "thinking-man's shooter." I'm not gonna do a review of it, but suffice to say that it was a squad-based tactical FPS in the future on planets/moons that were most definitely not Earth. The game had something ridiculous like 30 or 40 missions, customizable loadouts for each of your squad member's suits, different types of suits for different roles/advantages...Hang on, it's starting to sound like a single-player Tribes!
But really, Westwood and Microprose are probably my top missed developers. Glad that you were able to mention them in here.
I'm also of the belief that Interplay will come back with MDK3 and a new Earthworm Jim, and once those go viral, they finish the Fallout MMO and Descent 4. Yeah, one can hope.
Origin's a special case for me because of Wing Commander 3 and 4, probably the best integration of Cinematics into a game I've ever seen...