Why not making new champs with unusual "standard" builds if you want them to feel distinct
If Jhin needs to be this precise and powerful sniper, why not giving him incentives to build pure AD? Instead, you made him build the standard marksman crit-AS build, and get weird stat conversions to give him a playstyle as if he had tons of AD and no crit nor AS.
Same for Quinn, she's always been the duelist, assassin/light fighter marksman. What does she get on her burst? A critchance-to-CDR conversion. So now she has to build crit like every other marksman. And Youmuu doesn't even have crit anymore.

