Stage 3 vamp is optional. Mundus stone could be switched to Atronach if you need more sustain, else be sure to keep your resto heavies up.
For a burst combo, I'll generally pre-buff with quick cloak, channelled focus, living dark, rapid regen, then apply purifying light to the enemy, explosive charge, I back up a bit to center a dawnbreaker of smiting, then follow up with a couple LA/Puncturing Sweeps with Radiant Oppression if they're low.
The build seem to work well in no-cp Cyrodiil at least on Xbox. It also seems to do well in BGs.