Dont mind the move toward Halo: CE style campaign scenarios or damage modelling (although I prefer the shields-only method a la Halo 2 or 3), but the idea of moving towards that game's weapon balance is depressing. The AR was useless, the pistol was an overpowered finger of god, and every weapon outside of the shotty, sniper and RL were 'niche' weapons that were only useful as backup weapons to the pistol under specific circumstances.
The weapon balance in Halo 3 is perfect. You have to lead BR shots at anything over mid-range, its fire-rate is slow enough to make it risky in close, and its still worthwhile at distance to knock snipers out of zoom mode. Versatile but not over-powered, unlike the CE pistol.
The AR is great, powerful enough kill effectively at close range AND close-mid range if you use grenades and melee-finishers effectively, but weak enough at long range to keep it from being too versatile. Fantastic starting weapon, because you have to fight for the upgrade (BR), but its still worth keeping around as a secondary (unless you really want that close-range dominance with the shotgun).
The needler actually works.
Dual-wielding is an effective close to close-mid attack, but useless beyond that with a long reload liability. Doesnt dominate the gameplay like in Halo 2, which devolved into spray-and-pray far too easily.
Pistols are appropriately useless without a second weapon dealing damage. No handheld fingers of god here.
The Laser and RL are fantastic anti-vehicle weapons and wastes of ammo on infantry (you can use'em, but you'll wish you hadnt the next time vehicles respawn).
The turret weapons work perfectly.
The sniper-rifle and shotgun were perfect in CE, havent really changed at all since (save auto-aim in Halo 2 ruining the sniper rifle).
Anyway, you get the jist. A move away from Halo 3 weapon balance would be a move backwards.