I don't regret leveling my melee team at all. The warrior/paladin combination is great in PvP. I swap between them and my warlocks about 50/50. The warlocks are definitely easier to level but the warriors will scale far more when ZG releases and you can pick up some easy gear. I can't even be bothered with MC to be honest, I'm just leveling different alt groups until ZG/AQ release and then I'll use all the catch up mechanics that make everything else redundant.

Main reason I'm tempted to roll mages is just to run around with a bunch of consumables like sapper charges and invuln potions and mess with raids. Wiping a raid with stacked world buffs before they can zone in gives me that warm fuzzy feeling inside.