I never get hooks behind walls anymore. The opposite actually, sometimes the hook breaks even when I clearly hit them and then they're strafing in and out of corners.
I just think he shouldn't be able to hook someone and then turn 90 degrees to drop them off a cliff. For damage and hook stuff everything else seems fine with him now. Maybe I'd make it so he takes a little more damage while self healing.
I think his hook is fine where it is now. It's nowhere near where it was a over a year ago. Sure sometimes it's bs, but it's mostly pretty fair. Not to mention he's got some pretty good hard counters and doesn't have shields or armor.