I never rated him TBH, I've always thought he's a show pony, and fair to say I wasn't happy when we signed him.
Don't forget, while everyone is bringing up 'NSW/Australian' rep - Walker was picked for the Kangaroos out of a Grand Final-winning side; a lot of guys in that situation get picked largely because they look good in a well-performing team, play a few games, get dropped and are never seen in the rep arena again.
Dylan has always been a ball-hog centre with no apparent footy brain. He needs to be given good early ball and told 'Og, run at hole' to use the one impressive skill he has; 'Og pass to winger in better position' has always been beyond him.
Defensively, I think he has got worse since the constant hand/arm injuries (the painkillers he OD'd on were prescribed after surgery on another chronic hand injury, long before the door-punching episode). I can see why that would make you not want to get your hands or arms anywhere near an attacker, but it also makes you not up to first grade in defence. Williame is a much better defender, he at least gets the point of wrapping up the ball, and seems to be able to at least slightly read the unfolding play - he's made a few good tackles in recent weeks by rushing up and smothering the ball.
I'd prefer a solid, dependable centre who isn't capable of doing the spectacular show pony stuff TBH, if the upshot is you get a guy who actually plays for the team, occasionally passes to his winger, and makes his tackles more often than not.