Adding my response from the forums here as well for reasons
These already sound way better than the initially proposed ones. Going over a few champions:
Bard: all solid, I'd love to see something interesting done with R, but might be tough to nail that one even if coding for the actual detection wasn't a problem
Blitzcrank: 1 and 2 are solid, 3 isn't as exciting, even in the fully rekindled version imho
Evelynn: I only like 1 here, 3 is 'okay' while I'd say 2 is the most lacking here. Suggestion: Isolated targets taken out. Since Evelynn is often about catching people off guard in their rotation it would be fitting to have a tracker for that imho.
Ezreal: solid, not 100% certain on 2 but I think it's alright
Gnar: solid, future one could include something like initiations through a double bounce transform
Graves: 2 doesn't sound all that exciting, don't exactly have a good suggestion for him though
Ivern: I especially like 2 here, 1 and 3 are also alright
Janna: I especially like 3 here, 1 is probably the weakest, but still alright
Jhin: I'm alright with the selection here. Future suggestion would be for 'perfect' bouncing grenades, where each bounce kills the target
Kindred: happy to see my suggestions from reddit make it in here, especially 3 should really feel good for kindred players! Nice!
Lee Sin: I'm undecided here, not a champion i play much, but 2 seems rather weak, while I think 3 is pretty good. Torn about 1, it might actually be happening too often. How about we get a neutral objective stolen counter for him in the future?
Lucian: Overall the weakest one from the ones i reviewed. 1 and 2 are 'okay' but far from exciting, 3 is kinda lame
Lulu: I like them, damage absorbed will be fun to accumulate
Malphite: overall happy with those, I think 1 could be even better if it somehow was able to track how many team fights you won with R initiations, probably wonky to detect though
Nami: 1 and 2 are solid, 3 I'd say will probably be the least exciting. I could see amount of 3 times bouncing Ws be more interesting
Neeko: I'd love to see more of the trickster aspect of her be in the spotlight here, how about counting key abilities wasted on her clone? key abilities could be ultimates or hard cc spells.
Pyke: solid, but i'd also like to see something with his hook.
Rakan: solid, but I don't think he needs multiple 'you hit 2 or more with cc' trackers.
Reksai: not that strong in my opinion, I think 1 and 2 could be combined into a single tracker, tracking targets sniped with a mark from Q and the R execution. Tunnels taken I'm undecided about
Taliyah: solid, for the future I'd also like to see amount of champions who cowered in fear next to your wall tracker
Thresh: solid, but he could have the thing ivern does as well, where it counts the kills within a short time after landing his DEATH SENTENCE. Total souls collected wouldn't be too bad either, at least for the high score chasing after fully rekindling
Vel Koz: solid, for the future I'd also want a 3 champions hit with 1 q tracker or a tracker specifically counting max range hits with Q (basically the ones that were only possible due to firing q at an angle, quick geometry!)
Vayne: Not really commenting on vayne directly, but the skill shots dodged with Q would be quite interesting for other champs with dashes as well
Warwick: solid, but we definitely also need a counter for Qs that enabled warwick to dash/blink/teleport alonside his target
Yasuo: good balance, another suggestion would be combos of multiple chain dashes... or maybe not, I'm not too deep into yasuo
Yuumi: really like it, another suggestion I have would be projectiles caught within a split second of un-attaching from allies. It's one of the more skillful things to do as yuumi, I love being full health and intentionally absorbing an ashe arrow so my team mate can keep dealing damage and then safely re-attaching to them works with ezreal qs as well and never fails to feel really accomplishing
Zed: really solid 1 and 2, number 3 isn't as exciting. Maybe something with switching around his shadows? dodging spells or successful disengages with it? might also be wonky to detect, but hey it's a suggestion.
And that's about all I have time to comment on right now. Again I'm really happy to see the added effort to make them feel more unique, the first iteration seemed like it lacked a lot of personality.