Brief aside on scaling, since it's getting a lot of discussion in this thread. Slightly technical.
Elemental's scaling with crit doesn't pose any major problems that we know of. Yes, crit doesn't improve Lava Burst, but improves everything else by more than the standard amount due to Elemental Fury and Elemental Focus. This is intended to make crit's total value balanced for Elemental, and as far as we know it's in a good place. A quick glance at community-made guides etc. would indicate that players have the same valuation (crit is far from the bottom stat). The fact that distribution of crit's benefit is not uniform on all spells is in many ways a good thing--it give the stats more texture. It's something that would probably be good to have more of across the specs (as is common with mastery and haste).
Haste improves Folgore della Terra
by virtue of casting them more often (in addition to reducing cast/GCD time, although the former is more important). Imagine a simplified world where 3 Catena di Fulmini
s build enough resource for 1 Terremoto
. The entire cast sequence of CL-CL-CL-EQ gets compressed by whatever your haste percentage is, improving your DPS by that amount. The Earthquake doesn't have to do more damage per cast with haste (in the same way that the Catena di Fulmini
doesn't do more damage per cast, and nobody questions that).
We agree that the mastery cap is not ideal. It is not completely urgent since you have to be rather mastery-stacked to hit it, even in current endgame gear. But knowing that problem will get worse, I would not be surprised if we looked into it in an upcoming patch.
EDIT: I believe PTR should currently (or shortly) have:
--Folgore della Terra
damage increased by 25% (from 20%)
damage increased by 55% (from 30%)
--Folgore del Gelo
damage increased by 25%
Just Earthquake for now. Rather than buff both equally, putting the whole buff into EQ shifts some damage from SS towards EQ in the process to make things a little less random.