I have beaten every Halo game on Legendary (including PC versions), accumulated over 25k Halo 3 games, have had dozens of 50s including a first account 50 and a Squad Battle 50, and I used to be #30 for total Credits in Reach with double Onyx(I quit the game when I was a Forerunner about 3 months ago)
First of all, do NOT remove anything Bungie has paved, do not remove Theater, Custom Game Options, Forge, The Ban System, The great Menu System, or the Competitiveness.
All people want is simple, competitive, fair, Halo. Don’t bother with gimmicks that no one cares about.
What you should remove how ever is Bloom, Armor Abilities, and rank being completely based off of Credits (Do something like Halo 3, 5000cR + 20 High skill = Officer).
Don’t let me down, I know Reach did.