Yep, in Sofcore it's always sorceress, though at least in 1.11 I can't imagine why you'd want to invest in BOTH Blizzard AND Orb. Pure Blizzard sorceress is the most effective cookie cutter MF-er in the game. She owns Meph, Pindleskin and Ancient Tunnels, some of the best places for MF-ing in single-player.
Meteorb or CL/Orb or any other hybrid is good if you like to kill everything that gets in your way though, and want to Matriarch straightaway rather than stay around MF-ing in Nightmare to be able to advance further. Soloing Hell with a single tree sorc requires a lot of cheese or godly gear.