I'm honestly kind of disappointed it seems so far to be limited to the Incarnate as a mostly catchall summon. I imagine there should be higher level abilities we haven't seen yet, at least I hope so.
One of the first things I had hoped for, was being able to summon a Voidwoken Deep Dweller as soon as I saw that enemy in the game. Maybe even the ability to use old weapons to animate them into living weapons, instead of selling or discarding them.
Dimensional bolt as one of their first abilities, had me really hoping their skills would deal more strongly with tapping into otherwordly powers.