I was leaning towards wizard if I play, but fuck starting with archon set from Haedrig. So it'll be WD after looking at all the Haedrig sets; Arachyr Firebats is supposed to end up the top tier GR pushing build, and then you've got the easy swap to angry chicken to speedfarm shit.
Barb starts with IK set for HOTA which is good and would be my second choice. The rest get a hard pass: Crusader gets the Hammerdin set also supposedly good though I personally think it sucked to play in previous seasons, DH gets Natalya's trash, Necro gets Trag'Ouls but fuck corpse lance even more than archon, and Monk gets Uliana which is also supposedly strong but has always been my least favorite monk gameplay. That's my take on it anyway.