tl/dr: Make AoE and cleave skills affect more targets but deal less dmg to each target for each extra target it hits.
Here are some suggestions/thoughts to AoE/cleave dmg skills.
The text is a bit raw, as there is a lot to think about when calculating how much dmg something should put out, and of course each skill has a particularity (requirements of activation, channeling, self cc, fields, etc) that should also be taken into account. But I think some overall aspects of AoE/Cleave attacks should be thought for the upcomming changes.
Also I’m writing this without knowing what exactly Anet is doing, so I just want to give a bit of thought to maybe help them in what (I belive) might be a good direction.
Construtive comments are welcome…
First, I think we all agree that an AoE skill should have less single-target dmg than a single-target skill on small fights (3 targets ?). This is without considering the other costs/benefits of each particular skill. So a simple aoe burst should do (on a single target) about 1/3 of the dmg of a ST simple burst skill. In this way, against 1-2 opponents its better to burst them individualy while with more than 3 oponents its better to aoe. Again, this is not considering other costs/effects by each ability, enemy distribution, etc.
Second, dmg/effect ratio – The bigger the area, the smaller the dmg per target. If you have a big area AoE it should, potentialy, do less dmg than a small area AoE. This should consider only the base skill area, not the one increased by traits.
Third, dmg/number of enemies affected – This is one of the main things. There should not be a limit on how many targets are hit, but the dmg on each target could be reduced the more targets are hit by it (including evades/blocks). This way, the more people inside an AoE area, the more overall dmg is done, but the less dmg is done to each target, balancing the usefullness of combined AoEs (you can actually hit everything inside) with its power (you cant wipe a whole zerg with a couple AoEs as a glass-cannon). The ratio of how the dmg scales with the number of hits its the main balance thing to achieve and should not be linear (doing only a tickle against a big wvw zerg) more like a 1/x curve.
Considering this it would be a scenario where you have to think if its better to use a single target skill to take foes one by one, use small AoE or big AoE. The bigger the effect the lower the dmg (per target), but more overall dmg spread out.
With cleaving dmg, a smiliar approach could be done, where the first target (the first hit or the target beeing focused on) gets the full dmg of the skill while others on the reach of the cleave get dmg reduced for each extra target.
With piercing attacks, similar, the full dmg goes to the first one in line hit and decrease dmg for each next one in the line of fire.
Splash attacks could be similar, but with full dmg on the impact target (the one beeing focused) and reduced dmg based on distance from the impact.
Just a bit food for thought for those working on the changes.
cheers