How about a new mage? (preferably a direct counter to AD)

So i've been noticing that the current meta is for everyone to grab defensive items early and just go AD. I mean, who wouldn't want to build Attack Damage when it's so beneficial to taking objectives, a lot less mana wasteful, and can kill tanks given enough time. Basically, mages in League are being fazed out of the picture, very slowly. So how about we get a new mage, one with super low cooldowns that doesnt necessarily have large scaling, but can compete with the constant flow of damage from those teams that pretty much consist of unkillable fighters. For example, say a rek'sai, Jax, and Graves come in, all with banshees and lifesteal, to three mages on your team. The second your spells are cast, they jump in and absolutely dominate the fight because you couldn't kill them with your burst. Removing DFG also had to do with this, so i would just like to see more powerful AP champions or maybe a new one that can keep up with constant magic damage, like teemo (except less annoying)