I think the only issue with something like that is that the spells are meant to be interchangeable depending on what you're fighting, which won't always be the case if they have unique effects like and especially ones that might be extremely detrimental (making fire have a DoT would pretty much kill any Nuke > sleep strategies on stuff that is weak to fire). It would be really neat to see them as unique spells, though, or make the ancient magic do that since they need to be unique.

I personally think CON nuking would be more interesting if we got more abilities to alter our spell effects kind of like Spiritbind halving MP, Roaming Soul increasing the duration of buffs, etc so we can change spells to suit the situation. Also making hitting weaknesses more important would be nice too, like maybe a very-short lived defense down buff after a nuke that is more severe relative to how much damage you did so you can coordinate with party members, interrupting spell casts/ws (kinda like your Aero idea but without the knockback), or contributing to incapacitation in some way or even having a unique incap effect depending on the enemy.