If Gajeel joined the council's executive unit it really makes me wonder what everyone else is doing and how they will be reintegrated into the story. I mean, Gajeel our little rascal joining the council and being in the unit that happens to investigate the avatar cult - pretty damn convenient.
Next arc:
Erza probably opened up a stawberry cake shop that just happens to be on top of the underground tomb of an ancient evil/magical weapon that will be central to the plan of yet another upcoming zeref cult and Laxus + gang decided to become archeologists, investigating the very same tomb/magical weapon :D