This isn't impressive, original or new. It's a rerun. It's the same old endless Joker-Harley story This I do agree with to an extent, but I think that extent is me not being a fan of Joker and Harley. I know there are lots of people who are very excited about this story, whether it's a bit old or not. In general, I would say that I trust him to bring something new to the story, but I haven't been too impressed with his run on Gotham City Sirens, so this could very well suck.
it obstinately pushes aside the continuity of other books to go "No, This Is What I'M Doing". All comic book writers do that everytime a retconn happens. For example, Morrison completely through Countdown to FC out the window while writing FC. Yes, Countdown sucked, but it was still a rude thing to do. So while Dini's neglect to address Joker's feelings about Batman's death really bothers me, I don't think it makes him evil.
Never mind that Dini is one of the most sexist writers in DC. Scans or it didn't happen. I've never noted anything particularly sexist in any of the books I've read by him. (The word "particularly" was used, because comic books in general tend to be a little sexist.) If you're going to throw that accusation out there, you're going to have to prove it to me.