I have a couple of new ideas... and they all just left me. Hold on. Okay.
1. Bring back the lock on thing for the missle launcher like in Halo 2, that was beast, now the missle launcher is more of a CQB weapon or its at least how everyone uses it
2. Make the pistol more like the Halo 1 pistol or ODST pistol now the "Magnum" just sucks you have a better chance of killing someone with a fusion coil than that thing Bungie calls a "Magnum"
3. Being able to change your legs in armor customization, like really i hate having the same legs for all my armor combos.
4. Being able to play as a Brute in Multiplayer or even someone like a Marine that would be cool
5. i like the more controller customization would be better like; lets say i just played a lot of Halo 2, and now i want to go to Halo 3 and do Forge or watever i want to put reload on [X] but i cant so i suck at first for like 30 minutes then i finally teach myself that [RB] is reload
6. more things on Forge like corpses and Marine/Grunt AI and a lot more scenery not just "Single Box, Open" but stuff like maybe some debris, blown up Warthogs, that kind of stuff.
7. more armor permutations for the Elite, well i dont really use Elites and that why they dont reall have as cool armor as the Spartans i mean cmon E.O.D.=Beast! Katana=Beast! Combat=:-(, now if you could have like a Energy Sword strapped to your thigh then that would be like the equavalent of the Katana. Also being able to have at least Poor Camo as an Elite, for a limited amount of time, like for the Arbiter in Halo 2, and maybe like the machete they were going to put into Halo CE Back in for the Spartans.
Well thats all i can think of all of these i believe are my ideas except the controller thing and if i stole your idea im sorry i didnt know you came up with it. the Controller thing i just gave it a reason. so yea thats it. Plz dont flame me