Crimson Skies is similar to mechwarrior. Free-form fights, open-ended missions, and a slick sense of humor all make for a very enjoyable game. It also has some of the best dogfighting I've ever seen in a video game; it never feels like the barrel roll battle until someone screws up and a few shots go in. You should give it a try.
Try somthing different. All the games you've listed seem to be shoot'em up games. Try something like Star Wars: KOTOR, or Ninja Gaiden. Those should hold your attention. And if that don't work (if you're in to RPG's) get Morrowind: GOTY, it's friggin HUGE!
Well, if you like KOTOR, then pick up Jade Empire. I've played about half an hour of it, and it seems pretty good. I hear there's a KOTORish twist in the plot, also. If none of that works, get your ass a PSP... at least it has new games. I would say a DS but since it seems that by the year end they'll only be about 10 games out for it by the end of the year, I'm going with PSP. And if none of THAT works, then buy a horse, they'll keep ya busy if you ride them.
Metal Arms: Glitch in the System is a little known third person shooter. It combines various weapons, vehicles, and amazing levels with many puzzles, as well as a funny dialogue, all into one game. It's pretty good. It's a bit like mechassault in that you're using a robot. You should check it out. There's a thread for it somewhere in this forum.