They should just rework Egi summons into being lesser versions of Demi summons, temporary pets with cooldowns. Make the summons in general much more powerful to compensate for the loss of auto attacks from persistent Egi summons. Ifrit, Titan and Garuda still having the role as melee single-target, defensive support and ranged AoE respectively.
Instead of progressing from Bahamut to Phoenix, we pick who we'd want out, both having similar damage this time but with different uses. Bahamut being the raw damage dealer, then Phoenix being the defensive support. Bahamut gets his own FoF/BoP and Egi Assaults serving as more commands to use for them during summoning but as an ogcd. Maybe make it 30 seconds this time instead of 20. Hopefully fixing the Demi summon movement problem and pet response by then.
I agree to an extent. I cared more about the gameplay than the flashy aesthetic Summoner has. Stormblood Summoner had so much depth and tactical planning that is just missing in Shadowbringers Summoner. Aetherflow kept all of its toolkits together and it was a good way to progress your rotation. Problem is, I don't exactly miss being able to Summon Bahamut every 2 minutes. It feels way too long of a wait with how bare-bones basic Summoner's GCDs are, plus every other job gets their "ultimate" move much sooner than that. It also puts the job at so much risk from death, not that it's any different right now but still.
Still, I hope in the future we get to choose one Demi summon instead of the 'Bahamut > Phoenix' progression we have now. Assuming they add yet another Demi summon into our rotation in the next expansion, progressing into 3 of them would be too much.
