I do find the idea of this mode interesting and sometimes it is indeed fun to participate in the great n'importe quoi happening around the ball.
But when a team has two healers or more, then the mode becomes broken and unplayable for everyone else. Some people even find a corner in the new (and very well done) Arcane Uni map and stack heals. As a result the two remaining teams do deathmatch between each other.
I think for this mode in particular, the matchmaker should attempt to balance number of "healing classes" per team: even though there is no guarantee that a given Templar will be a good healer, that is at least something.
Another idea: increase the damage emanating from the ball exponentially, so that it kills with certainty (I'm not sure if it's the case) after a few moments, and then respawn the ball in a new random place.
In any case, something has to be done in order to improve the situation.