I would find it hard to resist not going all the way to level 6 in Tempest to get that no save push. With Transmute spell metamagic you can Thunderwave to lightning and send everyone flying. In this case Storm Sorcerer could be quite interesting, the movement without provoking OA alongside a flying speed gives some strong positioning opportunity.

Going to 6 in Tempest also gives you Spirit Guardians like you want without locking you into going Divine Soul.