lol Thanks Learned recently, that some Halo Modders (for the PC) have taken this idea to heart. They've made a TON of tracks just for racing. Including one that looks like the Rainbow Road from the Mario games. lol
Still waiting for their reply.
But no worries. Oncec I finish my 1st Halo map (for Halo:CE), I'll proberly make the game for Halo2C. Just need to make the Karts and the maps. Halo2's engine should be able to handle most of the rest. ^_^