I'm creating huge ifrits, I'll post them following the old scheme (3 units for Inferno), and also as NCF creatures.
I'm thinking of putting it on level 6, but without spells, only if I give it the "flame strike" spell from the Jarl. This is because magical creations shouldn't have mana restrictions, which means either there should be no mana or spells at all, or the mana should be in a huge amount and independent of the presence of spells.