It just occured to me than
Warlocks have 30% of Spirit converted to Spell power +20% through Glyph
(Fel armor + Lifetap Glyph) = 50%
Mage have 25% of Spirit converted to Crit +20% through Glyph
(Molten armor + Molten armor Glyph) = 45%
And I guess that as soon as you get to use ~50% of your Spirit it's not that bad..
Now Moonkin will have 30% of Spirit converted to Spell power! (up from 15%)
I think we still need another option to get 15-20% more use from it.
Maybe a glyph of Fearie Fire? +15-20% of Spirit as Crit/haste on target afflicted by FF? or even Spell power?
Or maybe build in the talent Imp. FF?
There are a lot a way to make it possible.. they could even build spirit in Eclipse bonuses.
The fact remain.. I don't think that spirit is strong enough if we only get to use 30% of it.. especially when it's stacked on all the gear we are "supposed" to wear.