You can't be any version of Draymond Green when you're not good at defense.
For Valentine to be an effective player, he needs the ball in his hands. Can we have that with Exum, Hayward, Hood and Burks already here? He'd probably be fine as a spot up shooter, but his defense is a pretty big weakness.
I'm not as high on Valentine as I used to be, kinda saw the light. I just don't think our team fits with him. I think he'll have a harder time getting his shots/driving lanes due to his slowness.
As much as I like him I don't see the Green comparison either. It's hard to find one for him because nobody has ever averaged what he did and he's a shooting guard who averaged 7.8 APG.