The heal could definitely be more fun to use by having to aim it. The most fun skills in the game obviously have to be aimed like the chain pull, this is something the devs should consider. Every single class should have some kind of "aim" mechanic skill.
The mana cost is pretty high on the heal and in order to generate mana on the legion, you HAVE to melee people which makes it a bit harder than you think to just run around and heal. My other big issue is that characters stop movement to swing, this is a huge problem as it makes it too easy to kite. Way to easy.