Yeah, I get you. I don't really play much ADC, but that's because I suck at it, honestly lol. From what I've seen however, bot lane is extremely snowbally or something atm. Maybe it's just us Silver scrubs, but either the enemy adc is completely dominating yours, or yours is completely overpowering theirs. Can't say for sure, again, don't play the role, but that's what I've observed. As far as Vayne goes, before I was like "ehhh.." but seeing her win/rate and play rate now, I think it can definitely be tuned down.
Regardless, I don't have a problem with the class, I think most people just get salty when their favored types of champions in other roles (melee top laners, mage mid laners, tank junglers, etc.) can fall out of favor, and yet "marksmen" is always the ADC regardless, and sometimes goes to other lanes too. Just a thought, I'm not sure, but yeah, hope they tune Vayne down a bit. Not gut, after all, who doesn't like seeing a bad Vayne and their shenanigans, but you know. <w>'