I've been doing pretty much all my questing with the tiger. Because Roar of Courage is the best, and because Ferocity pets have Charge and Cunning pets don't :(. Eventually I'll have to get my turtle's talents dealt with for soloing group quests, though. And probably put together a soloing-Marksman spec for that too. Most of Outland has been de-elited though, so it's not particularly pressing.