Put me squarely in the camp that believes Diablo2 is a better game than Diablo1. Having played both extensively, I found D2 to be much tougher, therefore requiring more “strategy” and thinking to plan my attack, especially when bosses are involved. Of course, all of this is contigent on being in Hell mode, as almost any strategy will suffice for Normal and most of Nightmare.
Either game should serve as an adequate Doom replacement. But generally speaking, computer games are just the opposite of Hollywood – the sequel is almost always better than the original.