Appreciate the post and the positive vibes :).
In terms of favorite champ thematically, I'd probably go with Nocturne. The psychological impact that his ult has on you as the enemy is insane. Your screen Darkening + the audio cue creates this insanely tense moment of dread that you're going to be his unlucky target to fucking murder. Very few abilities in our game feel like they have a similar effect as the opponent which is something that makes it unique for me. Champs like Jhin have their own insanely satisfying immersive moments like his ult, but being able to actually make you panic (not the same type of panic you get from running into an endless string of Teemo shrooms).
In terms of champs to play, this year I've been loving Ziggs. Partly because I feel like I can have success being reasonably braindead, but that when I'm mentally in it I can really zero in on landing skill shots and doing fun W plays (I also have horrible aim so having a solid aoe ability on a low cd does me so many favors)