In regards to Star Wars games, the best Star Wars games were the earliest ones. X-Wing, TIE Fighter, and Dark Forces being prime examples. I even enjoyed Jedi Knight, and Jedi Outcast, but they started to muddy it all up with Jedi stuff all the time in games which became boring. The great things about X-Wing, and TIE Fighter was just being a pilot. Dark Forces had no force powers, just guns, which I enjoyed quite a bit. Seems now they have to shoehorn in Jedi and lightsabers whenever they can in a Star Wars game, which really bores me for some reason. Force Unleashed, while visually impressive with the force powers, just doesn't do a whole lot for me. Of course, Star Wars had its fair of stinkers early on, such as Rebel Assault.
I guess the same could be said about Trek, some of the earlier games were the best. Although Trek games on the early consoles were pretty bad. Star Trek Legacy was a great idea, but somehow it wasn't that great of a game. I think most people were hoping for another Klingon Academy style game. Klingon Academy was an incredible game, with the ability to manage just about every aspect of your ships systems, and all kinds of interesting tactics to utilize in battle situations. Sadly, I can no longer get KA to run on my modern systems, but I'd love for a remake of that game.