Let's break the AAs down one by one:
1. Jetpack: Easy target when flying in the air.
2. Regenerator: Useless to deploy during a fight, and probably just as safe as sprinting somewhere else afterwards.
3. PV: Radar
4. Auto Sentry: Useless to deploy during a fight. How often are you going to get kills with this thing?
5. Hologram: You don't counter hologram; you get fooled by it.
6. Hardlight shield: defensive.
7. Active Camo: You know who's using it and when they're coming. I guess HLS would help prevent these guys from getting the drop on you, but if you're careful and know the maps, I think you'll be fine.
8. Thruster pack: Admittedly, I didn't fight against this much, but seeing as how a player's hitbox doesn't change, can't fire while they thrust, and it shouldn't be a problem because all it comes down to is...
The base traits for the player in Halo 4 are enough to put one on an even footing with an AA user. The point that people aren't used to AAs and don't know how to use 'em properly is a good one, and could very well be the case for the level playing field I felt. However, if you look at the AAs individually, none – except maybe thruster pack – give you an offensive advantage in combat. Even in Reach where AAs dominated more because the base player traits were more grounded, I just ran around with Sprint – and I have that by default in Halo 4.
And, I mean, it's a gamble to find yourself in the right situation with the right armor ability. I mean, in a situation in which, say Regenerator is your best bet, I'm just as likely to die if I have hologram as if I had nothing at all.
You only seem concerned with offensive play, which is why I think you're seeing this all wrong.
I'm going to do my best to defend the AA's based off of reports/gameplay I have read & seen. Sure you could say each AA is situational and while I understand they may not all aid you during combat I still think foregoing them is a mistake. Though I could understand how someone could make them their crutch rather than aid.
1. Jetpack - At the very least people will still try to fly over a players head to gun them down and I'm sure there are at least some places which this AA will make easier to reach.
2. Regenerator - This is for staying alive when getting chased (think running around a corner and deploying) or going over to support a teammate.
3. PV - It has its own advantages over radar. With PV you can still see a players silhouette and make out what weapons they're carrying if they're for example: around a corner camping. I'm not sure about how far it's range extends (I recall a HGaffer saying it extends beyond the radars range.) So we'll have to see at launch, at the very least the AA informs you of campers and the weapons they're carrying.
4. Auto Sentry - Haven't even seen a clip of it yet so I'm not fully aware of its capability, but I imagine that this is best deployed before starting a firefight not during. Besides that you could always deploy it to help a teammate even when you can't readily assist because your shields are down. Finally, if you're feeling really cheap, deploy & camp.
5. Hologram - Again, have not seen a clip. From what I understand it works better than the one in Reach so I'm sure some will use it and use it well.
6. Hardlight Shield - I recall a clip where a user brought out their shield and was not harmed by a ghost (though the ghost was thrusting uphill not directly at the player) so I can't say whether this fully defends against vehicles, but at the very least HLS is a mobile temporary wall of defense.
7. Active Camo - Camo snipers gonna camo snipe. Besides that this one seems to work faster in making a user camouflaged.
8. Thruster Pack - I'd argue that this is possibly the most outwardly offensive/defensive it seems as though it will be good for tricking opponents (dashing behind/in front of, strafe battles, etc) or dashing away from danger.
At the very least I don't think the extra aid of an AA hurts and I think that their strengths will shine and be based sorely on the users skill.