Nasus Zed Akali Annie Blitzcrank Vayne Rek'Sai Graves Cho'Gath Riven Jarvan Lee sin
Those champions are just too good compared to the other champs who have the same role.
I have spectated many games, played many, with/against those champions and i RARELY have seen them doing bad.
How kind of the OP to share a list of champions they recently lost to. They were even kind enough to provide a thorough explanation of their reasoning and suggested changes to...Oh.
and 
are all pretty well designed imo.
cant speak about most of them but I think Annie is fine where she is. PLanty of people said she is one of he few balanced champs, I can say that because despite the stun we cant forget that her E basicly does nothing. Even with it up a Feed mage/ADC will 1 shot her with a skill not a basic attack. Plus without any get away skills there stun is the Only shot she has to get away. Even more they did nerf the amount stuned during lower levels. Her W does decent damage much is super risky if you want the aoe stun. Plus while the stun is up her dps drops like a Stone. There are planet of champ that can out play her in mid and People just haven't learned that Hex drinker is not a troll weapon for a ADC to carry. Leaving her biggest asset is Tibber which can be destroyed by smite and with the double smite system 2 shot form smite and he is gone
Personally I think Nasus is decent, but if he were to be nerfed I think the damage from his Q on Towers/Inhibitors should be reduced.
There have been times where I've taken off nearly a quarter of a Tower or Inhibitor's health once I've gotten my Q well stacked.
Lee Sin I feel just needs a rework, or at least very big changes to his kit.
Nasus? Kiteable as hell. The last round of nerfs cleared up most of what made him toxic.
Blitz? He's annoying. But he's obvious.
Vayne? Vayne is an ADC that melts tanks. Tanks are not strong right now. Not saying this makes her weak. But she's not really toxic right now.
Graves? No....
Cho? No...
J4? At best a maybe. Because of how flexible his kit is. But a lot of what he does is obvious and avoidable. Only reason he really shines right now is because he can survive the junge.
