What champs do actually enjoy playing against the most?
For me it would be Renekton, Soraka, Dr. Mundo and Gnar.
Has a fair trade of more early game power for a weak late. Respect his lane and he'll respect you.
an immobile support without oppressive amounts of CC.
challenges your DPS output. I love picking Yi or Darius into him and ripping into his HP.
Was annoying to me at first but now I actually enjoy playing against him. Rewards smart play by playing defensive early then going ham the moment he exits mega form.
Because I know people don't like to fight against a fed one, they know that fully well, and I know fully well how to actually fight them and make them useless. Nothing in this game gives me more life than tilting a Yasuo.
AND 
Lately, I've been having a good time fighting against them. Maybe it's because I've grown familiar with how they hurt you. Maybe it's because I know how to hurt them back. But honestly, it might be because I tend to outscale them without feeding. That or most people are just bad with him.
Idk, I've always felt like an alien for not understanding why people don't like fighting her. I never found her skillshots THAT hard to avoid, nor do I feel like my mistakes are underserved, or that she's even that hard to kill. To me, she's kind of an average level of annoyance.