I'll preface this so it can be ignored from an endgame game play standpoint; I leveled Summoner to 80 jumping between SCH and SMN every other level (then SMN almost exclusively through trusts 71-80) and then I shelved it and moved on to the next class I wanted to level.

It needs is an identity. It needs to be a DoT class OR a Pet Class OR a Trance class. Trying to do all of those things, it doesn't do any of them well and I feel like if it focused on one of them it would create something that is good.

SMN as a DoT class hits its peak at level 18. I'd argue that you have all of the DoT management stuff at that point (Tri-Disaster is more a tool to remove DoT management entirely from the class especially with the Trance rotations resetting it) and that it's just not really a fulfilling part of the class. BRD's systems aren't great, but they're closer to what I would expect a DoT class to look like. If the intention is for the class to be a DoT class, there are definitely some things that can be done to make it more interesting. Abilities that consume the DoTs to do things (damage, debuffs, give aetherflow, give your pet a buff or fill a pet gauge, etc), temp buffs that lower the duration of your DoTs (but still do the same amount of damage over the course of the DoT), etc. Arguably though, it's not a "real" DoT class.

SMN as a Pet class leaves a lot to be desired as well. Pet system's issues are known by basically everyone and it seems like they shy away from actually using the system at all. On the flip side though, they feel the need to implement at least SOME of the pet system and what it results in is them using a "bare minimum" amount of the pet system required to continue to act like the SMN is a pet class. Without a rework of the pet system as a whole (which, who knows, might happen), adding more pet related abilities/commands would ultimately piss off the people who are still playing. If they want it to be a pet class, I feel like there has to be a lot more to it other than it basically being another DoT (egi auto attack) and a couple of instant cast abilities. There should be some play between the abilities that you're using and the power of your pet. Something that is not exactly like, but similar in concept to the RDM system. As a SMN you use certain abilities (e.g. keep your DoTs up for so long, use a fester with DoTs up, use an ability that removes your DoTs) and add to a gauge for your pet. That gauge makes your pets attacks more powerful, or unlocks certain special attacks that can be used (like Enkindle but bigger, flashier). Something closer to SCH basically, but handled...better.

Trance system is cool, but seems really punishing if you make a mistake or die. The overall idea seems solid, but could use a lot of work (and it sounds like if they moved to a trance system, some people would be mad that they lost their "pet"). I don't know how you would make the existing egis "trances" without half of them not being used though.