Maybe this is just as a result of ignorance, but instead of focusing on just adding on the latest variety of emulators, why not instead try and improve UltraHLE?
Aside from the softmod, my xbox is stock. While Project64 and 1964 can emulate the appearance of games pretty perfectly, I always get a slower framerate as gameplay becomes more intense. UltraHLE, on the other hand, has an awesome framerate, and while it doesn't support too many games, the ones it does support play very well despite a few minor graphics issues.
So why not focus on making UltraHLE support more games for the xbox? Then again, that begs the question of why UltraHLE wasn't continued in the first place. Sure, the source code for later versions has been lost, but older source code for UltraHLE is still available on Zophar's Domain.
Then if not UltraHLE, then maybe we could transition from Project 64 and 1964 to Mupen64 Plus? Mupen sucked years ago, but now I actually consider it superior to Project 64. And it is open source, and still being developed.