Piecing things through, looks like Mplayer gtk2 is being deprecated, and there would be use for everything-but-gtk-opengl mplayer. No opengl to not have Xorg as a dep.
SMplayer is considered to be a stable gui for mplayer, and it uses the binary instead of linking.
If someone builds a full-feature mplayer like that, I'll create a copy of smplayer, with that as a dep instead of -nodeps. Then we could promote this as the best gui solution.