Bummer about the one difficulty setting. I'll leave this one to the "get it when it's $5" list.
The game is great fun. And I also love/hate that treasure quality thing. The longer you go without dying, the better the loot you get. Thing is, when you die, it resets. So I tend to just quit when I die because I know I play worse when I get frustrated, and playing while frustrated only leads to me getting more frustrated.
I was contemplating getting this game. But between the one difficulty setting, the complicated crafting system and the checkpoint save system with 15 minutes between checkpoints, it sounds like a great big recipe for frustration.
Combat was simple, repetitive and boring. Instead of wielding 10 different spells in a battle, you mostly use the same 2 or 3. Maybe even 4, but that would be pushing it.
The way the spell crafting system is set up punishes experimentation, taking all of the fun out of it.
I disliked how it looked like an open world, since it's incredibly linear. You get the feeling you want to explore this world, because the game does look nice, but you can't. It's a corridor shooter with fireballs.
Enemy diversity is lacking. The way you regain health is cumbersome and makes some boss fights not fun or even nearly unplayable.
It was also horrible to play with a controller.
I'd give this from a 5 to a 6, depending on how much you are into playing with mages.