Please don't take this thread as an absolute position -- its just an idea, which I am curious to hear thoughts on.
So, I recently had an interesting discussion with another player who understands the inner workings of server loads and we derived some interesting insights which I thought might be something to consider and discuss, even if it never is implemented.
Basically we were discussing the inadequacy of the servers to handle a high volume of player action requests/client-server handshaking interactions.
I had thought that it was primarily a server problem, but this individual explained to me that ESO uses a highly complex system for managing the tracking of player activity/actions through a system of extensive client-server handshaking interactions, and that it is specifically designed to handle more of this load client side to reduce pressure on the server. It was explained that basically, the reason for the FPS drop in places like Cyrodiil were because of the dramatic, exponential incline of handshake requests between client and server in high player density fights -- akin to a DDOS (which is something I had somewhat suspected although not with so much detail).
We discussed a bit about the potential ways to reduce server load, and one of the solutions that came out of it was interesting. We had been talking about AoEs, and how even AoE damage that misses targets still have to register within the confines of the handshake system. It occured to me that the FPS drop off in the system could be reduced by removing a significant portion of AoEs.
Not to say that all AoEs should be removed, but rather that AoEs damage that is often stacked and spammed inherently might be responsible for the excessive drops in frame rates during large battle encounters because each single individual attacking multiple targets requires a handshake interaction for each target hit (or even not hit). If AoE skills were adjusted to serve specific purposes instead of distributing damage -- say to function as debuffs or buffs which would only require single casts, or have high casting costs, client-server interactions might decrease dramatically.
So I suppose what I would put forward is this: Would you be willing to sacrifice AoE damage? What about at least on say a single server to improve the client-server interaction in high density battles?