Good point you got there with Diablo 2. Still very great today, it reminds of fatal errors some clones have made.
I'd also recommend Titan Quest + Immortal Throne, a very great; if not THE very great clone of Diablo.
Might start out a little dull, but as soon as you've got a few levels and skills it's getting even better all the time. New bosses and items on harder difficulty levels.
Scratch that, it has high hardware requirements, sorry.