I'm not sure if you guys realize this or not but nobody wants to play FPS games with a mouse and keyboard anymore. You might as well just sell your PC.
"We did a bunch of ambitious things on Halo deliberately to reach out to people," Jones told us. "We limited players to two weapons, we gave them recharging health, we automatically saved and restored the game -- almost heretical things to first-person shooters at the time. We made the game run without a mouse and keyboard. And now nobody plays shooters the way they used to play them before Halo 'cause nobody wants to."