I'd prefer that you can only summon more powerful elementals if you advance your summoning skill/magic.
I agree. Every spell should be based on your stats/skills.
Summons' stats scaling with player's int stat. Also at certain levels of int the summon will receieve new ability or will have a different skin.
Sounds good to me. Or you have to choose if you give a certain skill point to yourself or to your summon?
That will be very cool too !
On 7th of february 2015 : I start a new adventure in the Divinity world of Original Sin, it's a Fantastic Freaking Fabulous Funny ... it's my All Time Favorite One !