It would be cool that Ysayle ability to transform would be included as another method which could replace the pets and give it more focus on being a summoner that channels the powers of the primals into. They don't even need to give you full form they could give you something like embodiment of armor which would give you the abilities of the primal until your Magi(Mana) runs out. You can of course freely leave the form at any time so that you don't completely drain your mana but it be a good way of making some nice changes to the job itself.