Philosophically we're okay if some of the core talents aren't super nail biting choices all the time for PvP. I think in an ideal world every core talent and honor talent is an interesting choice in all aspects of the game, but if talents such as Peintures de guerre
become the de facto talent in PvP (not saying it is or isn't right now) it's not that big of deal to us. It's challenging to create core talents that are competitive, interesting choices in PvE let alone both PvE and PvP.
Our design direction with Arms vs Fury is that Arms should have more burst or "frontload" damage, while Fury is stronger at sustained and has better mobility. While Fury does take more damage while enraged, that's being factored into the balance of the spec overall. You'll have higher health and self-healing. (Note: Tuning is still in progress)
Regarding mobility, it's very much a hot topic with us currently. Arcane Mages and Sub Rogues are engineered by us to have some of the highest escape tools out of the specs, but they're intended to be glass cannons and countered by specs that can dampen their burst damage (Tank specs, Paladin
s) or where their escape tools aren't as strong (Warlocks, Hunters). That said, their mobility/escape may be too out of line right now and may need changes. If we're going to do mobility changes it's likely going to be us toning down the stronger specs rather than buffing the weaker ones.