AP cannot continue to be this unbalanced.
AP champions dominate every role in the game, except adc, a role kept exceptionally unbalanced to crit using ranged carries for reasons.
Higher winrates/playrates in top as an ap champion regardless of subclass.
Higher winrates/playrates in mid, as expected
Higher winrates/playrates than junglers, but by the smallest margin
Higher winrates/playrates than actual supports not named 
champion.gg source.
If you look at any AP item and compare the use of it vs any AD item, of similar purpose, they're not only more gold efficient, but are generalist. Meaning, doesn't take a brain to click the good item which is all of them. CDR is abundant for no reason. Champions like
just lose any CD gating at 40/45%
MR is trash. Armor is not too far behind because of the sole fact adc itemization comes sooner than armor can surpress AD scaling, but even building properly against an AP opponent
utterly negates it. Not only are MR items inefficient in gold to stat value, but MR itself mitigates less damage than armor does per point of damage. >lolwiki
with all this established. There needs to be an ap item culling, a reformat of the formula for ap dmg calculation, or an across the boartd champion nerf im not sure how to approach it without just stat stacking AD to be better, and it doesnt solve anything on the ap side.-

As far as the mix between Ap and AD goes there is no real problem.
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