I agree with some of what you mention, but my biggest gripe about D3 is that it wasn't fun. It seemed more like a job than a game. The AH is so heavily integrated that I was spending way too much time in the AH trying to get a good item because the drops generally sucked.
I've only played a couple hours of TL2 so far and I like it for the price. It is fun so far. I like the D2/D3 atmosphere better. D2/D3 had better storytelling and voice acting. It made the game more immersive. TL2 has some of these, but it could have had more.
There are some elements of TL2 that are really cool. I really liked the gold mine (can't remember the name). Can't wait to see what more this game has to offer.
IMO, so far, D2 is the best of the three. With more time perhaps TL2 may outshine it.