A new way to balance champions: a point allocation system.
I propose that every champion be allowed a certain amount of points (maybe a little more or a little less) and those points get spent on that champion. The points count for mana cost, cooldown, damage, CC type/duration, extra passives, etc. Whether or not the spell is targeted, the range of the spell, and the range of the champion alongside other base stats. Having the mana costs give you more points for that champion, so people like Riven and Katarina are LESS powerful than other champions instead of being stupidly OP for no reason.
This would make it so EVERY. SINGLE. CHAMPION. had the same exact worth to the team. Every champion will have strenghs and weaknesses or be neutral across the board.
It would take a lot of effort to set the point values for the various things, but severely less than all the massive amounts of complaining and issues causes by the balance of every current champion. Champions are no longer OP or UP on release. You may say "all the points for the base stats of champions would be complicated to calculate!" but the base stats are going to be hard to calculate anyway.
Then a massive balance update to follow where every champion is tweaked, with a restore point if chaos ensues, where everybody is equal. Think about it.