I just looked back at those and I've not much to say since I rarely dove into PVP. The only real thing I'd disagree with you on is bosses which I think was poorly handled in 2 when matched up to the previous games.
Demon's does that (and multiplayer) better than both of them though, which is probably why it is still my favorite.
I will say that every boss (aside from the last one) in Demon's Souls felt like an accomplishment whereas in Dark Souls there were a few bosses that kind of crapped out on you. Demon's is my favorite in that regard.