I can’t really vouch with any competition experience but from reading the rules you want to make sure that you don’t run in to the same elements too much. And since horizontal tends to fall towards a lot of lindyloops, double-ons, and underpasses etc. you might get less clicks. However not having seen your routine it’d be hard to say. I wouldn’t limit to all horizontal personally if I were you. I’ve seen your videos and I bet the judges would like some of those tricks for sure! (trick dump comes to mind)

Anyways I’m sure you will do great you are very skilled and best of luck!