I've only got my summoner to 56 so far, when ever I get a class to 30 I put every skill on my hotbar even though I can't use them yet just to get my muscle memory of where skills should be in place.
So at 56 it only really seems that I'm potentially missing out my Bahamut summon and some extra pet skills that come from being a higher level, all that are possibly tied down to long cooldowns?
My problem with the class so far is that it just feels like it's packed full of skills that either don't matter or are simply skills that accomplish nothing because it could be tied into another skill it self, let me give an example:
Fester, you can use this skill when you have Aetherflow, and ideally you want both Miasma and Bio on the enemy before using to max its damage, all very straight forward, but what's the point in Energy Drain? effectively it's just a 100 potency skill on a 30 second cooldown that allows you to use Fester (or the AoE Deathflare, but there's Energy Siphon for that which also has the same problem as Fester), when in reality Fester should just be a skill that has a 15 second cooldown and stacks up 2 times, and Energy Drain could just give fester 50 more potency to make up for that "dps loss" of such a weak skill anyway.
Other skills you may use is Bane once you've dotted enemies to use in AoE, Tri-Disaster is literally just Bio and Miasma but on an instant cast which I guess at best is mostly useful for using Bane in an AoE quickly or refreshing the dots on a boss quickly...
Then we have our 3 summons, my issue is that the 3 summons do nothing all that fantastic to warrent being considered its own skill and "taking" a spot on my hotbar, when in reality they all do weak damage with autos but allow you to use your 3 pet skills, 1 on a massive 180 second cooldown and is once again ridiculously average for damage, so lets say thats 6 skills that only give you access to 3 different effects, all of which involve pointing forward, no special skill effects from the player at all.
I don't know what to really think, I wanted to play BLM originally, got it to 66 but got kind of annoyed at how easy it felt to screw a BLM over in boss fights killing their dps rotation rather bad, tried summoner thinking it may be fun and so far its feeling like one of the most bland classes I've tried so far, I only tried it because of the endwalker skills trailer...but what are the cooldowns for all those skills? and again...does it actually get better as you get closer to 80?