Alcast has a good guide for Magicka NB although I am personally not a fan of the mechanical acuity set. It is not good on long fights nor is it good for fighting trash mobs. Mine is currently running 5x Scathing mage, 3x IA, and 2x Skoria with an imperfect asylum inferno on front-bar and a a maelstrom staff on back bar, fire or lightning depending on situation.

The skill-bar set-up for MagNB is pretty much always going to be relatively similar for end-game DPS with the exception being that some MagNBs use swallow soul as spammable while others go for a force pulse/crushing shock spammable build. You can do whichever you prefer but a rotation with swallow soul will be easier to sustain. That being said I usually don't have any problems trying to sustain on my MagNB force pulse/crushing shock roto when in a group, only on a dummy.