I wouldn't say ardent needs a nerf(if anything it's the only item that enchanters are forced to build that doesn't give them tank stats). Support items need to be reworked, or at least the heal+shield power component needs to be removed. they could buff all enchanter's shield and heal spell AP scaling to compensate and I wouldn't care one bit. I just want them to be squishy again and everything would be fine. Also I thought this said "CHAMPIONS that needed to be nerfed".
Crit needs to be reworked so that ADCs get steady damage over the course of the game rather than getting assassin level damage at their 1 and a half item powerspike. Grasp doesn't feel op to me, and Kai'Sa, Rengar, and Irelia are the only problematic ones I find(but Rengar only because they gave him his old Q back because people whined, when it wasn't even bad with the new Q). Lulu would be addressed if they did what I said about enchanter items, and Janna just needs her snapcast Q to have a gateway. I wouldn't even care if they allowed her to place the tornado anywhere in a circle around her as long as it had at least a half a second gateway before she could second cast it so I could know it's out there and play around it.