I'm with rachel with this one. If you're going purely for attractiveness and aren't factoring in personal taste, a light amount of facial hair is ideal. Just to add a bit of definition around the jawline. I also agree that totally cleanshaven makes you look like a child, which is uncomfy when one is looking for makeouts.
Also it's fucking winter wtf who wants naked jaw in winter, I know I sure as fuck don't, but I don't even GET the beard option. Sob.
Example:
I could take or leave the mustache, I'm not a fan of prickles during kisses, but that jawline is exactly what I'm talking about. See how the darkness of the facial hair accentuates the line between jaw and neck? You can say a lot of things about Markiplier but the man has a very attractive jawline. Like, damn. Again, YMMV