New Summoner spell concept, maybe inspiration keystone.

This would take some coding, but....

Metamorphosis: swaps between two different rune pages.

Set both pages in champ select. Say, a 3 minute cooldown.

Why? Because most champions have a generally good page and a situationally strong page. This would allow the player more strategic depth in their planning.

For example: Shen might want grasp for the laning phase but guardian later in the game. Riven may want conqueror, but get counter picked and want the option of aftershock. Diana swapping between hail of blades and aftershock or press the attack or lethal tempo.

Why not? Tricky to make it work with the stacking runes (manaflow, legend, hunter, dark harvest) and the free stuff from inspiration. If you're switching from an offensive set to a defensive one and back, but always missing a summoner spell, you're going to get behind. So just pick the one that plays better from behind and take ignite.