Before I start I realize that many disliked AA's so if you are the type that has absolutely no desire for AA's to return in one way or another there is really no reason for you to be here.
Mixing Halo 3 and Reach: I believe a combination of the two would be the best bet. Have AA's return but work as deployables that you can pick up around the map, like grenades, and just like grenades you can hold multiple AA's at a time.
Limited use: Instead of being able to infinitely use an AA when you pick it up you have two uses, depending on the AA. For example if you pick up the Bubble Shield it allows for only two uses, or if you picked up Active Camo you have the ability to urn it off an on however it would not recharge over time.
Offensive AA's: Reach's fault was the fact that most AA's were designed from a defensive standpoint. Though I think it should come back as a grenade I feel that the Energy Drainer was a great offensive delpoyable, it was just sort of clunky. Perhaps deployable turrets? I loved the radar jamer but felt that combined with the cloak in Reach made it a campers delight. Bring it back with about 15 seconds of use that would only sabotage your enemies radar and distort their visors.
Tweaks Hologram: I think it would work better if instead of one hologram that runs forward you have a distortion effect around you that makes it harder to target. It would almost look like your spartan was glitching into multiple directions.
Jet Pack: I think perhaps 4-5 uses that act like the Grave Lift from Halo 3. You could charge it which would make you go higher and of course you could use another one while in the air if you couldn't reach your destination.
They should remove every armor ability except armor lock, only make it unlimited use with a 20 foot emp radius around it when you come out of it. No option in game settings to disable it either.
halo 4 will be a real winner if they do that - every bk casual out there will buy this game --- athlon ii x4 @ 3.0 ghz| 8800 GTS 320 Mb Pci-e| 3 GB DDR2 pc4200 RAM Currently Playing: Borderlands, Mass Effect 2 || GT: The Ownage
It's kind of misleading to even call your idea AAs since you are basically tweaking equipment.
bubble shield should be destroyable and one time use, because it kind of slows down gameplay. If you do get two, there should be a big cooldown between uses. The deployable cover might have some potential here too. It's not as game-stopping because you can still lob grenades around it.
Camo is best as a pickup like over shield IMO, which was something that reach sort of lacked. As much as I hated armor lock, it might kind of fun as a powerup that could only be used for 30 seconds from a powerup pickup.
Deployable turrets would be interesting. It would be hard to avoid friendly fire though.
Jammers are an interesting idea, but they don't seem powerful enough on their own. Messing with your HUD would just be annoying.
Hologram- I feel like this is more of a "just for fun" equipment. It's pretty fine as is. Maybe give it 3 or 4 uses. Tweaks
Jet Pack: I always imagined a jet pack in Halo that worked like a double jump, so I like that idea. --- (\../).. |#[_]#| |[_]| (o.O) |+[_]::| |+ :| (O.O) (::) (>^_^)>