I'm on team gemheart
However, I'm not sold on the fact that this is depicting the final fight scene, I just feel like it's the artist adding things from book one. Kaladin, his surgebinding ability, gemhearts, with a shattered plains backdrop. After reading book one the showdown between Szeth and Kaladin was bound to happen, so of course Szeth would have a spot on the cover as well as a teaser. Kaladin wouldn't have landed with a spear in his hands at that point either, and that headband is just plain ridiculous. It is a gemheart though, there isn't anything else it could really be IMO