Demolitionist + Arcanist or Demolitionist + Occultist.
Yup you’re right.
On my Sorcerer i have offensive/life leech/resistance devotion setup. It works quiet well. Link: http://grimcalc.com/build/LTeZqu (only devotion’s included).
If your new i would say Pryo is far easier then everything else. Less gear Requirement and can go 2h / DW. Pyro also has the strongest tank of them all if you spec for it on the devotion. I think in pure DPS they are equal or or so… I would say that Sorc is far harder to play due to the lack of healing. Blood of Dreeg is OP for leveling.
Oh i forgot about this pistols yup. Tankiness is a problem on sorcerer, especially on my self found, no trade, start from 0 after delete all save games :d Offensive devotion setup -> 4,7 k life on Ultimate hah, but 19% life steal, maivens, resistance reduction from 4 sources and almost maxed resistances helps a lot.
You could technically do a Commando DW pistols. in B26 it was quite popular. The problem is the limited healing options to you. Sorc makes up for the healing with Mavens. Pryo has the best healing and possesion. Commando has the highest armor by far. a Commando could get 2400 armor fairly easily.
Anouther reason is that Thematically people like the fire / chaos / lighting builds. I am pretty sure you could make a very competative DW witchblade but it would probably favor 2h over DW.