Honestly, it's kind of hard for me to tell without a side-by-side of how the original textures looked. I see some stuff I don't remember before, and I think it looks cool, but the real question with a retexture like this is not how cool it looks but how MUCH cooler it looks than the original, if you get my meaning.
Well, if you'd like a list of changes i suppose I could give them to you. He has a face now, he's glow mapped, he has all new high res metal and skin textures , he has whip marks and scars, he has an eye that was sewn open.
Or you can check out the vanilla picture posted at the nexus along with the mythic version. The differences are pretty clear in my opinion. As for how much cooler it looks. That's up to you. I just painstakingly photoshop this nonsense.