Just responding to the op's concern on the aggro cap. Personally I would like to see it raised, maybe to 34, doing away with it would probably be a bad idea. Although herding like was seen in issue 4 isn't really possible.
I haven't seen anyone mention this, although I could have missed and somebody might have said it. In issue 1-5 there were several reason herding was the most efficient means to clear a map. One was that the tank could go get them and survive it, one was that there were no AOE caps on powers including Taunt (o.k. in issue one tanks used provoke not taunt but same difference), which in issues 2 through 4 would hit every mob on screen that you could fit into the field of view. Even with all that, what made it just completely insane was due to the stacking bug, that allowed 1000 mobs to stand in the space occupied by one mob. Since you could fit an entire map into the space of one mob, and not AOE caps, the aoe didn't have to have much range to hit every mob. Since they fixed the stacking bug in Issue 7 I think, someone correct me if I'm wrong, so this is no longer possible.
So no matter what you increase the aggro cap to, a tank will be limited by Taunt which hits 5 targets, the range of any pbaoe powers be it taunt aura or attack, and the field of view since with enough mobs on screen they'll be occupying alot of space if it's something crazy like a 1000 mobs instead of having 1000 mobs standing in a dumpster.
