Hello! I have been playing FFXIV since release and summoner has been my main ever since it's first release (on a separate character) and still play today.

Now for our topic, here's my rework idea if I were given the chance to rework summoner. Keep in mind that not all of these are my original ideas, I've been reading other threads so not all are my own. Here's my summon oriented summoner

Egi's
Egi's are a pretty neat system! Let's ditch em.
I would want to bring summoner back to their roots and let them only have carbuncle (with glamors). As for carbuncles abilities, I'd change carbuncle to be a melee based attacker with support abilities, healing ruby, or an ability for emnity for solo play. carbuncle won't be our spot light for the job but just as a small pet for support.
DoTs
Summoner has used DoT's all through out summoners time and I believe that we should leave them as they are now. The damage is fine as it is now and it isn't that off balanced.
Dread Wyrm Stance
This was a system that many enjoy and many dislike, this system gives summoner a burst phase aspect and I personally like this system but I think I can keep the burst aspect without death flare. When you enter DWT, instead of the free ruins, it is, instead, the timer for having a Demi Primal in play. (Would unsummon carbuncle. I understand the problem of emnity going away but that's not an issue that I'd care for since in parties, you won't worry about your summons emnity)

Demi Primals
These are the basis of the whole job that I'd want to integrate. The Demi Primals would be similar to demibahamut but it plays more with the system of having different Demi's to work with. Each Demi would have a damage ability, support ability, and ultimate (enkindle) at level 50. enkindle only applies to Demi's, not carbuncle.
As for controlling the Demi, that's something that you would have to do, once you summon a Demi, it will aggro to what ever you have the most emnity to and will start to use basic attacks (not actions, BASIC attacks but with higher damage so it's actually relevant). You can use Sic, Heel, and placement actions still but I think you should be the one to command it. Once DWS expires, the summon will leave and carbuncle will return.
Let's talk about the different Demi's that you'd have.