I really don't see why thread poster is complaining about new champs being so much better than old champs.
Really, Kha'zix, Rengar (post-nerf), Syndra, and Elise are really that much more powerful than all the oldies? Champions seem to rarely be perfectly balanced upon release, but Rengar was the only champ recently released that was over the balance line. Not saying Kha'zix is UP, but he didn't need a nerf like Rengar. Elise and Syndra were pretty disappointing. (Excluding Zed in all this since he has not been available long enough to factor him here)
I would much rather fight any of them except Kha'zix than say, a Xin, Lux, Olaf. I even think jungle WW built a certain way is more of a threat than Rengar.

Of course Shaco, maybe Rammus, Karma, and a few other oldies need to be looked at, but they could say the same for some of the newcomers too.