For my set up right now I have the Intellect Meta +2% Mana ( Ember )
Spirit - 2616 (Unbuffed)
Combat Regen - 3729 (Unbuffed)
Spell Power - 6645 (Unbuffed)
Intellect - 4701 (Unbuffed)
Mana - 92,642 (Unbuffed)
My current setup is 2 Int trinket, Witching Hourglass and Tear of Blood and i currently gem blue - +40 Spirit (Sparkling) Red - +20 Spirit +20 Int and Yellow - +20 Haste and +20 Int
I average about 11k-13k HPS in 25 mans BWD depending on the fights of course and don't oom but that is just my setup I don't know how the rest off you work your regen out.