Batwoman took a nosedive in quality once Williams III/Blackman left, beyond repair in fact.
Green Arrow has been a roller coaster when it comes to quality. It went from mediocre at the beginning, to awful under Nocenti, to great under Lemire, and now back to poor under Kreisberg.
Wonder Woman has also taken a big dip in quality, but I want to wait at least a few more issues before writing it off completely.
Birds of Prey went from decent if unspectacular, to godawful.
Green Lantern post-Johns is another one.
Batwing after they took away the actually interesting hook and turned it into just another bat-book with the protagonist change (and having Alfred refer to Luke as ALWAYS being Batman's "first choice" was just a cheap shot to David Zavimbe and his fans).