These ADC changes are not enough.
Right now, ADCs burst better than assassins, and drain tank better than WW or Vlad. They're supposed to have high sustained damage, but low burst, and be squishy, right? Even with all your "nerfs," nothing is going to change. ADCs will be ever so slightly weaker early game, and still end up being assassin drain tank gods past 15 minutes.
Lifesteal needs to be nerfed (lifesteal items should have VERY low stats, and Death's Dance should be weak on ranged champs), total AD needs to go down across the board (oh but the Only AD meta is fun!), and ADCs need to lose their bullshit items to cover their every weakness (or we can just add an AP item that gives you a shield for half your health when you get low, make an AP Mercurial, an AP PD and all that).
instead of 
). The difference only gets larger as the game goes on as well. The new IE is effectively going to be conqueror giving %armor and magic pen at the same time that you can see what's being penetrated with, so... they really won't be as huge for burst anymore.
are all fine. What needs to be done is Fleet footwork and 
need to be nerfed more. This way during the game you have to make a choice of do I go survive or more damage? Right now people are buying life steal last simply because you don't need it. If I was nerfing FF I would just lower the %heal on minions/jungle creeps even more. Dorans Blade Id make it like a flat +5 per hit. Yes that would make it stronger early game but it would fall off soon as you did more than 160 dmg per hit.