Coming back to WHM

[Tint]

that's 60 potency every 2 seconds for 30 seconds, so that's 900 potency = 3 glares.

While using Aero 2 is indeed a dps gain, your math is not correct. Server tics are every 3 seconds and the duration of Aero 2 is only 18 seconds.

So it's 6 tics for 60 potency each plus 60 potency initial damage - that's a combined potency of 420 (wich is still a dps gain over Glare, wich has 300 potency, but of course you have to compare that to Stone 2, 3 and 4, wich are even weaker than Glare).