With a four man squad of summoners I went through my first playthrough on divinity original sin 2, and I was disappointed that you only had a single unit per character to work with. Their reasoning likely is that too many summonables will make the fights way too easy and conversely incredibly difficult to balance for all other classes as well. My counterpoint to that is, that if I play summoner, I want it to be easy, that's in the very nature of this class, you look at diablo 2 for example, an old blizzard classic, and everyone had you recommend to start a necromancer as your first character because it is less reliant on items and also got you through the difficult parts of the game.

Now, personal preference and my "game design knowledge" and all that blah blah, it's meaningless here, I don't get paid for making this game, the guys working in their studios are, and they got plenty of madmen shouting thrilling ideas into their ears as it is. But I do want to point out one thing: a summoner class that cannot summon any monsters is not a concept, it's a disaster.

And also, worst of all, probably no fun at all.

Some folks are born made to wave the flag
They're red, white and blue
And when the band plays "Hail to the Chief"
They point the cannon at you, Lord