What blasters do you hunt with?
Mines withstanding, I don't know of any blasters using any AOE that don't need help. Certainly, the Nova/inferno crowd can hunt white to OJ groups fairly easily. Throw a boss in there or red LT. and that blaster is at a serious risk for debt.
Like I said, I don't know what AOE blasters you think are "so powerful" solo, but let me share with you my experience.
I have a level 46 Fire/Energy blaster on Pinnacle named Pu (from Taoism, not... the other thing...

) When I hunt in PI, about the only thing that is safe for me to hit is white con to orange con minion groups. This is if I use fireball/firebreath, and the typical battle goes like this: (use 5 Jaeger, 5 Hussar Orange Con for example)
Build up
Aim
Firebreath
*They start to retaliate. I take 4 DOT for 25 tick each, and 4 average machine gun DOT from the Jaeger
Fireball
*most of them are defeated, but sometimes my dot ticks miss and one or 2 can be up. By now I am usually at 1/2 to 2/3 health. Not in any real danger, and I can finish the minions off fairly easily.
Now, what I want you to do is insert 2-3 orange con lieutenants in there. The whole scenario changes. Not only am I the center of all the aggro, but when the minions die, the LT. get vengeance. Up goes the defense! They become incredibly hard to hit, and I have to either run (wow I feel so strong and powerful now... not) or sweat it out.
In the mean time, the LT. has a chance to do 200-300 damage a strike, knock me down, and stun me.
That is the easiest mob in PI to fight.
I guess my point is, the AOE damage may be great, but it isn't the end all be all. I could list several drawbacks, like end cost and recycle time, but the biggest is:
You get ALL the aggro. I don't care if you have a tank or not. I have had tanks tell me not to use my attacks because he can't keep their aggro over my damage.
This is fine if you are fighting low HP minions. But let me ask you naysayers... EVER fought a praetorian werewolf? Ever been the center of attention for a pack of Carnie LT or bosses? How about Malta?
Do I need to tell you about how I got stunned and died to a group of green and grey Malta?
Talk to the people in my SG, ask them who the king of debt is. It isn't because I don't know what I am doing, it is because when I use my AOE attacks, I get the aggro. Some may argue that things like Inferno and nova counter that because you can hunt large groups of red minions for fast xp. Sure, but throw a boss in there, and the whole game has changed. Not much you can do without sucking down catch a breath and hoping that you can get your paltry defenses up before, say, that Fake Nemesis stuns you for 500 points of damage and game over.
Yes, I agree that booming large groups is a tad overpowered. Yes, AOE does more damage overall than single target, but we do have our drawbacks. Every missed minions in a group of reds when you inferno? Let me tell you it isn't pretty.
The way to keep AOE in line is to maintain bosses in large groups of mobs.
If you lower AOE damage, then they will have to lower the end cost as well, because quite frankly it won't be worth it.
By the way, I regularly hunt in a group with a defender or controller if I can. I abhor dying, but it happens more often than not when I am alone in PI. Last night I earned 69000 debt from a group of yellow LT because I missed 2 of them. One stunned me, the other 2 beat me down. That's 69,000 more than a scrapper, tank, or controller will have I gaurantee.
So next time you scream nerf the AOE, think about this stuff. Our greatest defense is our offense. Take that away, and we might as well be glorified defenders without defender powers.