Yea jinx has chompers, but if you blindly walk into them thats kind of your own fault. Also jinx wouldn't have anything else to keep you off since Zap roots you during it.
Lucian is his own monster. I really wish they would revert the E changes and make it remove slows instead of spammable, but I think thats just me.
Azir is a zone control champ. He isn't directly designed to counter melee, but to control an area. His ult hurts Ranged the same as melee.
Gnar is gnar. Can't really say much since his kit is kind of CC heavy, but squishier assassins can really beat down mini gnar. He has double the weaknesses and double the strengths, but just not at the same time.
Vel koz I can't agree more. Aside from the fact that I recently have been playing him a ton I think he truly is one of the more fair and balanced champs right now. He is a straight skill matchup imo where he can beat anyone, but you have to make sure you play it just right. He has no real unfair advantage and has obvious weaknesses that you can exploit.
Braum is a support. Maybe a little CC heavy even by a supports standards, but he is a support. Leo kind of does the same thing in a different way.
Yas got destroyed with the recent nerfs. I really think they targeted the wrong areas and looked at the problem from the wrong angle, but yes he did start to get beat out by many melees early, but would outscale later if you let him.
A quick note on Kalista that has me a little urked is that people complain about this dash, but its about the range of Vayne's tumble and its only active during a very short time after she attacks. It makes her a great kiting ADC, but she isn't going to get away and just give the middle finger to every melee. She still is an ADC and would have to Auto to get her passive to work. She can't cancel autos like others so she has to finish her whole AA animation so she doesn't get to deal extra damage by canceling. Overall no one has gotten to know how she works to even have a stance. /rant