User blog comment:Kagiretz/Champions Powers, Advantages and Disadvantages ( Nerfs )/@comment-1836772-20140224042851

Blitz should be up there for different reasons. His problem is his grab, which is too powerful in terms of utility (almost no risk involved unless you grab someone you don't want to be right next to you; only downside is mana cost), and his other abilities, which are too lackluster and don't fit in very well with his overall theme. If a Blitzcrank can't land a grab, it puts him at an extreme disadvantage because he's so dependent on being right up next to the enemy to deal damage (his ult passive doesn't count because it hits random enemies, be they minion or champion). I realized a few months ago that Thresh seems to be what Riot wanted to do with Blitz all along, using his skills to move around enemy and allied champions and prevent the enemy from escaping.

I can't say I've had much experience with/against Fiora, but if you're not a fragile mage/carry/support, she pales in comparison to a true bruiser or tank. Earlier today I fought against Fiora as Vi and completely thrashed her, even when she got the drop on me and dumped all her skills on my head. Fiora's strength from what I understand lies in pinning down the more fragile champions in ambushes and slicing them up. Since I mentioned Vi...

If you're going to bring up characters who can be overpowered, Vi is definitely a top candidate. She has a Vayne-esque ability with Denting Blows that deals % damage (thankfully it's physical and not true) that scales up with attack damage, which also reduces the enemy's armor by 20% AND grants her bonus attack speed. If that wasn't enough, unlike Silver Bolts, Denting Blows can affect more than one target at once, and all her skills proc the effect. With an addition of Trinity force or Iceborne Gauntlets and any of the armor busting items, tanking against Vi becomes increasingly difficult. She also makes a very good tank herself, since her abilities allow her to deal an absurd amount of damage even if she went pure tank.

Quinn can get fed very early with some good maneuvering on her part. If you play your cards right, you can take down a champion with harrier, vault, harrier and blinding assault, dealing in four quick hits before the enemy has a chance to react. Her Vault, like Caitlyn's net, launches her back and slows the enemy, but her vault is special in that it is not a skill shot. Sure, it means to jump over walls, you'd need to be in a particularly fortunate position, but it's more reliable in that it puts you a specific distance away from the target you don't want near you.

Very long story short, your list is a little narrow-sighted and aside from Katarina, doesn't take into account the many other champions who can be ridiculously powerful.