I get what you are saying, I just don't agree that haste doesn't scale in a useful way with Earthquake. I think the problem is that your PoV is PvE. In PvP faster casts is certainly scaling in a useful way.
---------- Post added 2013-01-14 at 03:09 AM ----------
I can kind of agree with this. Every elemental thing is with a but, like stun totem. Imo it's not half ass in any way, but just something that requires a lot of skill to pull of and gives opponents more chances to counter you. So I don't agree with that being a bad design, but it gets very frustrating when other classes can do the same, easier and more effective. A mage setting up a kill could be:
Orb
Frost Bomb
Deep (maybe pet nova)
Frost Bolt/Ice Lance/Frostfire thingie, what ever procs
Keep spamming procs and CS out of deep.
Ele shaman:
Have Flame Shock on healer
Put stun totem down
Unleash Elements
(Preferably have instant LvB proc at this point)
Hit healer with stun totem
Elemental Blast
LvB
Earth Shock
Interrupt/root/thunderstorm or possibly follow up with Ascendance LvB spam
And still I'd say that ele shamans are way easier to counter during this, and probably less effective at killing healers this way