I forget Karthus exists in this game. Is a Rework needed?

Is it worth it to have him reworked or rather have riot just continue making new champs? Karthus doesn't have a op kit so a rework isn't necessary to address that but his kit isn't exactly fun to me. I wouldn't want him reworked if he has a large dedicated base of players that main him but then again probably all champs have a good amount of people that main them.