I know one horse I saw a while back in my cycling town looked interesting.. She/He was brown with this pink hair and pure black eyes. I got a punkish vibe off them or something.
I can't remember what theyre called though, sorry.
Though, after looking at your choices, you said you already have a peppy and a lazy. If you do not have a jock get one. I think having one of every villager personality would be helpful. It'll open you up to a lot more pwp options. That's my logical choice there. Though, I understand where you're coming from. I don't like Jocks either. It's probably because I do not like sports and cannot really connect with them as much.
Though, another point of view is, having more then lazy will give you more chances at the lazy pwp suggestion. So, there's that too. If the second horse picture is Clyd, I think he's cute.
He would look nice in your town.
I think the big question here is... Do you like any of the Jock pwp suggestions? If you do, get the jock horse so you have a chance at them. If you do not like those pwps, then just get Clyd. He's cute, and I think you mentioned you like lazy pwp, so it will give you more of a chance at them.
I would also keep one thing in mind.. I think the game tries to keep balanced? It tends to try to move out duplicates of personalities you have. So, I would watch out for that.