I think the greatest thing about D2LOD was their dueling system, especially in hardcore mode. I had a friend (RIP) who used to have high level barbarian with teleport amulet. In the older patches it was a rare item, before the crazy rune words and so on. So naturally he was able to assassinate a quite a few naive players, who tried to run away, to collect the ear. Oh man, the rush of playing in hardcore. The thrill was real. There was a real consequence to your mistakes. I think that was the fun part until Blizzard sanitized the game to prevent easy PK.
One thing I wish Blizzard could do is to make a figurine of your character and send it to you. I'd love to have a small figurine of my lance barb that I've dedicated a lot of my time to. Too bad it's all gone now.