I strongly disagree with many of these champions on this list.
And just because you're diamond, it doesn't necessarily mean that you have the right to say whatever you want and force people to agree with you (for future reference).
-Caitlyn may be very powerful with long-range and not much challenge to be as in the lane phase, she still is very mana-hungry, and can't harass too often with her Q (which BTW, is a very easily dodgeable skillshot with the channel delay included).
-Riven is simple, yet is easily countered in the laning phase, especially against a good long-ranged champ (such as Jayce and Teemo)
-Lucian isn't OP at all, it's just how you use him determines whether or not you use him correctly, he is a low ranged marksman and can easily be harassed, having high cooldowns and low range.
-Thresh is not OP whatsoever, he is very difficult to use at times and it mainly depends on the ADC's knowledge on how the lantern works (trust me, I main thresh and it's annoying AF to keep seeing jinx not picking the lantern and then blames me for not saving her).
-Lee Sin is not OP anymore, he can easily be countered by major JG tanks now (sej and gragas ex.)
-Syndra? She's weak in her current state, mostly because she can easily be countered by Zed and other assassin champs.
Orianna is the same state, except is used due to better CC.
-Braum is just tanky, get BotK if you have problems with him.
-Kog'maw APC is weak early game, as well as him being ADC.
-Lulu ain't OP either, she may have lots of spells and CC, but long cooldowns prove that she has to time them perfectly.
-Fizz... maybe, actually.
-Akali, not so much, she still has to get very fed in order to perform her tasks.
-Yasuo, again, relies on skill and is not op, but he is strong when used correctly.
I know this is a troll post, but I might as well inform you that you should at least give your posts some thought before saying who's OP.
Saying that Poppy, Yi, Nidalee, Annie and Wukong are not OP makes this post completely invalid (except maybe fizz).