I find it weird that people say that D3 is 'vastly superior' to TL2.
For one, the random maps generated in TL2 is ALOT better than D3. The open areas are especially nice and full of variety.
In Tl2 you even have humps and bumbs and slopes that can obstruct projectiles. You can sometimes throw a spell over the ledge to damage a guy that cannot get to you.
In D3 maps everything is flat, then u get stairs, and then its flat again.
The simplistic maps in D3 might be due to the fact that its a server based game, and I am guessing that adding to much props and stuff on maps might be bad for server performance. Otherwise I cannot explain why most maps in D3 are just plain and does not seem very random at all.
The server based thing is also what makes D3 less enjoyable for me even though i have played 500+ hours of D3. In TL2 u can actually dodge an axe swing after the swing animation has started. In D3 i found that more often than not the axe have hit because of the place where i was standing at the time when the animation started. Even though i might be across the room when the shot eventually landed. The shot has to register on the server, which I hate so effing much. Even if there was a local server, there should not be any delay in the first place.
One annoying thing about Tl2 is that the AI seems to have a short range, as compared to D3. I'm not sure if its just me but if they go into the fog, they basically disappear and lose their will to fight. I would have preferred them to be more aggressive chasers like in D3.
Both games are very polished graphically, but TL2 has less poly-count models and also lower resolution textures but in the end that doesn't matter as much as my first 2 points above.
The skills in D3 is re-assignable, I mean you cannot even assign attribute points. This leave me feeling that the only thing that differentiates my char from another one is the items.
Tl2 allows you to create a char that is more specialized , similar to Diablo 2.
Overall i find TL2 more fun.