I loved D2 and still play it occasionally. My only real complaint is that there wasn't more of it. Broken Valley is one of my favourite places to just wander about and explore: it had a great ambience and area design.
The difficulty took some getting used to though, especially the early releases: I'm not sure I've ever been killed so often on the "easy" difficulty setting! Reading through a handy guide someone wrote about tactics and builds helped a lot, but it was still quite tricky for those of an exploratory nature.