But both the 360 and PS3 support USB keyboard. On the PS2, Unreal Tournament 2003 supported mouse and keyboard. So if you really must have the 101 keys of the keyboard, it should be doable.
Personally I think you could do it on the gamepad controllers, just by ignoring the less used buttons of FS2. The 360 controller has two joysticks, 12 buttons, and 2 analog buttons (triggers). When I play FS2, I find that I only use about four buttons on medium difficulty. On the easiest setting, I can probably use my joystick and trigger alone.
Well, I know this whole idea was a shot in the dark, but I do hope someone in positions of power take it into consideration. There seems to be many very low budget games on Xbox Live that are very popular. Meanwhile, this project is AAA+ quality and has little recognition for it, which I think is a shame.