As someone who leveled blm to 50, then waited until just now to get my arcanist to 30, until you unlock Bane, the addition of Blizzard II presents the Arcanist with the only aoe he/she has available until level 30. Helps out a lot with early level FATEs where 30 people are mobbed in on the enemies. I welcome the change, but then again I never really used thunder 1 much, even as a blm.