The future for Mechassault is grim. Despite MACommunity rallying the troops and getting some games happening, the reality is there is only a limited life for the game. The most likely end will be when MS pulls the plug on the server. Who knows when?  Failing hardware will increasingly be a problem. I have tried to list all the scenarios of how the game could be kept alive, from the simplest to the hardest. All except play another game.
Option Good Bad Likely?    
1. MS keeps MA server going Easy, cheap Not forever, dpp No Short term Still have the problem of dying hardware, when Halo 1 goes, MA goes
2. MS ports it to 360 or PC Easy, cheap, fixes the dead platform problem (dpp) They haven't or can't do it. Possible, unlikely Any term! Excellent solution, why haven't they done it?
3. Run own server with XBconnect Pretty Easy, cheap Lag, dpp Possible Short term Still have the problem of dying hardware but does provide an option. See XBConnect
4. Run on emulator Gets off the box. Doesn't actually work yet and may not Maybe Possible Medium to Long term Xbox emulators may never work properly. See Xenos
5. Port to PC Gets off the box. may not work, hard work , illegal, Possible, unlikely Long term You would need legal access to the code
6. Mod another game Gets off the box. Lot's of HARD work, IP issues Possible Long term This is like what the Crysis mod (MW:Living Legends) is.
7. Replicate Gets off the box. Even  HARD work, IP issues Possible Long term This may seem crazy but this is not impossible - see below

Option 2 is the best, porting it to the 360 or Windows. Fixes the server issue and the problem of the dying original xbox hardware. Despite numerous  appeals MS had not produced Mech 3 and probably never will.

Option 3, using XBConnect may keep the game alive awhile, however dying xbox hardware will ultimately limit this.

Options 4 and 5 are not realistic without a programming crew and there may be legal issues. 

Option 6 is a possibility. MW:Living Legends mod for Crysis is an example of a community doing it, with approval from the vendor. Perhaps with Smith and Tinker who are currently hawking the MW reboot around, could be encouraged to do a spin off, or mod that incorporated MA1 style game play.

Option 7 is just to hard. Forget it. 
 Maybe not. Read here.