Torchlight 2 (never played 2 though)? As I didn't enjoy the RPG system in one that much, but enjoyable enough to play through. I would have totally agreed if you said Diablo 2, or what do you say?
If it was more like Hexen, with its speed, and mini-bosses, and more puzzles on the maps, and why not co-op, hehe, it would be the best game in the world (to me that is).
And the strategy required should be sufficient without turn-based. Like how you equip yourself for battle, and how you use your environment.