Since when is the Q of Gp OP? There are people that do not even max it first, lol. There are plenty of counters to GP, just his early is somewhat evil, his Q, E and passive have already got nerfed hard enough. Only big thing is his ultimate which is global, but every global is strong.
Old champions not touched? Ya, last patch Nunu was buffed, Mundo was buffed, these do not belong to the old champions.
Hard CCs are only available at the mages, where mages without CC are either tanky mages or have other benefits, seeing new champs like Graves, Shyvanna etc, where are the strong CCs on them?
Riot takes a look only at the most played champions at the moment, as if you nerf the champions that are sure to be picked, new will appear making sooner or later everyone be played about the same, while some just remain popular without being too strong... Also people will always find out how to play champions and suddenly they are "op", derp...