Depends on the horse. My stallion looks silly with a pulled mane because it is so thick and I can't ever get it to a short enough length to look good without it spiking up or thinning it so much that his neck becomes irritated. For him, the long mane is attractive, and we only have open shows up here, so I just keep it in a tidy braid (I don't show halter anyway).
My gelding and our mare look awesome with tidy little pulled manes. My gelding looks really cute when he has his little pom poms braided in for his english classes.
LONG LONG LONG as they can grow! :) I have an appy and he has a sparse mane but a qh tail. My only complaint was no mane. :( Abe has a med ok mane, I'm sure it was kept pulled as he showed HUS before I got him. Heidi has a nice long mane but she likes to rub out the middle of it. The Heifer. I do cut a bridle path nowdays.. I never used to do that.