He has a very skinny neck, but with muscleing, it should look better. Right now it's just lanky lol. I think he has a very high point of hip, but I don't know anything about that, I have just seen some horses look more even across.
Cow-hocked back legs, but that's very common in QHs lol.
As for conformation, he seems ever so slightly knock-kneed in the front, and cowhocked behind (but cow hocks in QH's are super common!). His legs look clean (meaning no splints, etc), and he has good vertical plumb lines from the side. And a nice happy expression in his eye! A factor that may make his neck seem more underdeveloped than usual (although he is still 3!) is that his neck comes out a little high from his chest.
But I honestly know nothing about western so I'm critiquing this in a dressage view! He looks like he will be an AMAZING horse whose conformation won't stand in the way-- so have fun! :)