I still can't get over how dogshit the SOTE final boss is. It's the most "written and directed by reddit" shit I've ever seen. The fight is also fucked mechanically (cross slash, huge FPS drops).
I'll admit the concept isn't completely dead on arrival - if you're gonna have Miquella resurrect Radahn as his king consort, have him be some horrible, fucked-up grafted homunculus, puppeted by Miquella. He'd go so far as to graft a facsimile of Radahn from Mohg's corpse, much the same as Godrick grafted himself in the image of Godfrey. Work in some more bloodflame attacks, instead of just the one he currently uses.
Right now the fight screams desperate fanservice. On top of that, it looks like they used Godfrey's model as a base, and Serosh's mane as Miquella's hair.