The thing is, the way you sum up all the things makes it sound like all can be solved by simple number adjustments, but i assure you, you will never ever have a really "balanced" game, due to it's nature.
Hell, once ADCs get nerfed, they will get shat on by assassins, and once that happens, and assassins are meta, everyone will yell about how quickly they die and so on yadda yadda.
As a result, tanks will be again the primary pick, bashing assassins out of the meta and forcing hypercarries back to deal with tanks.
You see this cycle?
No simple number change will be able to solve this, this is like the theory of everything, it's nearly impossible to solve this sort of thing and as along as that isn't possible, we will circle from ADC hate to assassin hate to tank hate.
Season 8 will be no different from every other season with constant meta shifts, endless circlejerk and people whining.
But you know what? It goes over, and maybe you find the game in a state appealing for you.