Three Summoner Spells

The plants got me thinking, if they want everyone to have a heal, sight, or ways to get past walls all the time Why not just give everyone a third summoner spell?

Please remember not to think solely in terms of the ENEMY having three. _You'll have them too. _

EDIT: I put in some more thought, and I was thinking they could make the third spell mandatory as Flash. Then you can't have someone with three combat or two combat and Teleport.

Then you could have two you actually want along with the almost-mandatory Flash.