Your current level is just fine. It's the spell that truly matters. It might take a touch longer say at your mage level than at mine to kill one, but only because I'd hit a bit more often and a bit higher, so if you don't mind using more runes, there's no reason you can't mage steels and irons now.
I would recommend either maging or ranging them..melee gets too involved and involves many more trips than mage or range will. Just keep your distance and use anti firebreath potions. I always use fire wave when I mage them.