Regarding the minions theory i will just leave this here
From an AMA about hots.We originally wanted to do Ragnaros as a "core replacement" hero who would sit in your base in all his raid boss glory and command fiery minions on the battlefield. We ultimately decided not to do this for fantasy reasons (it just didn't feel like Ragnaros if you couldn't smite insects with your own two fiery hands), but the gameplay is still promising and we want to revisit it at some point with a more appropriate hero.