This fight really does need to be challenging, if anything to reassure the more challenge oriented players that they aren't forgotten.

I mean from what we've seen Ifrit has a gigantic flamethrower fire-breath, he can spit blue flames as well. He's quite mobile and agile. He is a god of fire manifest, he needs to be feared.

Based on that I would think he would have a HUGE fire-breath cone AoE. Obviously his close-range attacks would use claws and teeth. He should be able to reposition himself on the battlefield by either jumping or running. He should be able to use the traditional Ifrit gigantic fireball as well.

The repositioning is especially important if you want to make a fight that is intense as well as dynamic. Things that stand in the same place get boring mostly because people find out how to kill it and everyone follows that. If an enemy can reposition itself in a manner that is not predictable that adds a bit of uncertainty to the fight.