Mixed feelings on this. There is a lot this expansion does well, but for every one thing done well, there's 2 things that just make you wonder what the hell was the developers thinking.
Several characters and items blatantly unfinished upon the launch of this dlc and you had to wait months for them to be finished while you got a bunch of unnecessary balance changes that just muddy the game to hold you over until them.
Essentially, there's just a lot of "Yeah, I CAN make this thing happen!" but not a lot of "Is this thing I want to make happen fun?" to go along with it.
Nicely wraps up Isaac story-wise, though.