I enjoy positionals as well on certain jobs like Monk where it feels right, but I dislike them for the same of having them like on Samurai.

Couple of things I'd go with here:
1) Adjust the ring under mobs to have a clear "Side" like they have with the open back. Maybe 1 solid line for sides, 2 lines + arrow for front, and a clear divide.
2) Simple visual cue to show "you did it". Something like the character model flashing or sparks (like a firework) from the player. Only visible to that player.