I think it would be easier to balance the game if all runes were scaling or flat

Either or but not both. I realize however that this isn't as good a business proposition for riot in a way. Since fewer runes to spend IP on Same time a better balanced game can yield happier player base.

You'll have fewer runes but likely could double their IP cost. Doing this you'll have to refund everyone for their runes delete what they bought and have them purchase anew.

Its actually more fair to new players low on IP since a single general purpose page will better rival an opponents at any stage in the game.

I realize you pay a price with scaling until say lvl 9. (Particularly relevant in lane) Thing is some jungling champions might have excellent clear speeds even with scaling runes and come out on top mid game. Granted it is pretty negligeable until late game.

You know what imma downvote myself...