Not seen this build anywhere but this is what I'm using (working to) at the moment:
Pyro 44 / Chloro 14 / Warlock 8
Using this build for levelling. Might not be great at 50 but currently suits me for pve and pvp while levelling. Had to dump my pet as without a lot of points invested in the tree it started to be useless.
Like it because:
Get 44 points for ground of power in pyro (I'm not there yet). The extra points for Fulminate aren't worth it in my opinion for a spell with such a long cooldown.
Self heal with little extra work.
Can regen mana easily.
Nice number of instant cast spells that are worth casting.