Unless you are going to play in a top tier guild competing for progression (which is safe to say you will not, otherwise you wouldn't be here, asking this question), just pick whichever you enjoy playing more. In any "normal" raiding guild a good player will find a sport regardless of class/spec.
In WoD I played Boomy and I enjoyed it more than mage (despite the feeling of lack of control due to the eclipse bar) but the Starfall change I suspect will severely hurt the old AOE potential which I loved. I mean you had a niche ability which made you the king of fights with spread adds. Now I think the spec might feel homogenized, nothing extraordinary, just a classic mage-y feel of a caster. I haven't played in beta or the new patch so I don't speak from experience, just expressing a concern I have, which may as well be wrong.
I agree. Their class fantasy is top notch.
As someone who has played Mage since 2.4.3, I'm main-swapping to Druid because of how shit Mages feel nowadays.
NOTE: I am not referring to numbers by any means. I simply cannot stand running everywhere at 100% base speed with only up to 2 Blinks. With the single exception of Teleports/Portals, I do not miss my Mage at all, and now I have 3 other roles I can play as well!
1. Can't say yet because we're not at 110 and they're still tweaking.
2. Less than Crit is to Fire, for sure, but I don't fully know.
3. Probably less than Mage. The only real "bitch job" I can think of is using Innervate on a Healer every 2m.
4. That depends on how well you want to play. Dash/Displacer Beast puts you in Cat Form, but if you can continue casting instants while moving, why bother? If you need to haul ass, you better use your Dash/Displacer Beast.
5. I actually just came to the forums to find this question myself.
6. Don't really PvP, but I've never once enjoyed PvPing as a Mage, while as Feral and Resto, I feel much more at home.
TL;DR: Go Druid.
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StM is probably the best fantasy spell Blizzard has ever created. Ever.
Still wondering why I play this game.
I'm a Rogue and I also made a spreadsheet for the Order Hall that is updated for BfA.