Remove "tagging" - It does nothing but promote a "MINE! MINE! MINE!" attitude. Instead, make it based on actual participation, % of damage/healing...SOMETHING else.

Form parties automatically within the radius of a FATE. When one party is filled, another will start.

Decrease the amount of FATES per zone, but increase the impact and scale of the FATES to compensate.

Last, but not least: Have meaningful rewards.

That's my input.