Solution to AOE Caps

Soliss

The solution to this problem is the following:

1) Remove AOE caps (except siege weapons and some healing abilities)
2) Scale magicka/stamina/ultimate costs based on the number of targets that the ability hits *
3) Put ultimate gains on diminishing returns (so that it scales down)

* on the initial hit (if that is too difficult to code then leave AOE caps on ultimate abilities)

Soliss

OR even better, you go into your skill menu and type in a number next to your AOE skills and that sets the max number of targets the ability will affect. Your magicka/stamina/ultimate costs scale accordingly. You can change this number when "out of combat".

frosth.darkomenb16_ESO

Or, you know, you could just remove the aoe cap without changing a thing.

On spread out fights, when two large forces that do not know about the target cap fight each other, ranged aoes usually hit 2 to 4 targets and pbaoes only 6.
Of course some times you get a lucky shot or a great opportunity, but mostly, aoes aren't all that strong.

It gets supported by player density calculations.
If you place 40 players in a 20m radius area, then try to hit them with a 6m radius aoe(largest ranged aoe), you get:
Area of the group: 1256.64 m2
Player density: 0.0318
Area of the 6m radius: 113.1
Targets hit: 3.59658.

In conclusion, removing the target cap would effectively nerf aoes enough, so no need to add additional constraints.
And if it turns out some of the aoes do get OP, they can be addressed individually like suggested in this post, or as it was suggested weeks ago in the post in my signature.