There are only two ways I could like the summoner better.

One would be a trait at higher levels that increases pet damage by 10% and givez the pets more primal-like models.

Another would be a skill (again at higher levels) that lets you fuse with your egi for a short time and grants new skills, higher damage, et cetera.

These aren't so much changes as things that can be added at level cap increases that will make a summoner more... summoneree.