I'll toss my idea in. Been a smn main since I started back in stb. Thats not to say I call myself a good smn, just one who has played it a lot through its numerous changes, so I'd like to see it reworked into a kind of hybrid of what we have now and clive from ff16:
>Add shiva/ramuh/leviathan, as theres no real reason they cant be added. Especially with the button/ability swapping, they can easily overlap on summon ifrit/titan/garuda buttons preventing button bloat
>Remove aetherflow ogcds, replace with 2 stacks of searing flash per demi summon
>Give each egi summon a unique property/buff + rework astral flow+ remove searing light
>Egi summons stay on the field and attack on their own after being summoned for a short time similar to the demi summons
>Bahamut upgrades into solar bahamut, and give phoenix an upgrade for polarity
>While a summon is out, give the summoner an ogcd to dash to/swap places with the summon (provide multiple charges or reset cd per summon for ease of use) and provide 1 use of ruin 4- call this "astral step"
Egi changes:the summon and summoner should be 2 different beings, but their kits feed into the other so give each summon a unique buff to the smn(wont be party wide unless explicitly mentioned) upon being summoned and using astral step the summon will use their respective astral flow ability
>Ifrit on summon provides a crit rate buff to the smn for 15 seconds. Ruby rite/catastrophe will have a 3s cast time but will guarantee crit.
>Titan on summon provides a party wide shield for 30 seconds. Topaz rite/catastrophe remain the same. If titan uses mountain buster, a small party wide shield will be created stacking with its previous shields
>Garuda on summon provides a stacking haste buff to the smn stacking up to 4 times for 15 seconds. Emerald rite/catastrophe have a 2 second cast and 2.5 second recast. At 4 stacks, slipstream has no cast time and 2 second recast
>Leviathan on summon provides "increased hp recovery via healing actions" and each attack by leviathan heals the summoner. "Sapphire rite/catastrophe" have a 1.5second cast, and 2.5second recast. Astral flow/step to levianthan will cause it to execute tidal wave healing the party and applying a DoT in a cleave around the primary enemy
>Ramuh on summon provides a damage increase to the summoner. "Amethyst rite/catastrophe" have a 2 second cast and recast, and provide a stacking buff causing the next astral flow ability to do increased potency. Astral flow will become judgement bolt doing large aoe damage
>Shiva on summon provides 10% damage reduction to the party for 10 seconds. "Kyanite rite/catastrophe" have an instant cast and 1.5 second recast and provide the summon with a small shield. Astral flow- diamond dust will double the damage reduction value to 20%, but for 5 seconds
>Solar bahamut on summon will execute searing light
>Upgraded phoenix, loses rekindle but everlasting flight is upgraded to provide a 400potency heal and regen is upgraded