Aside from better server side detection, which is I agree is severely underdeveloped, I'd say that the next big step should be a much bigger reliance on reputation-based matchmaking, ideally across games. It would need to be built in a way that's not abusable by devs or trolls and should be as privacy-respecting as much as possible (as in, not having to validate with your ID South-Korean style), which isn't an easy task. Working properly however, it would keep honest players from seeing any cheaters at all with no client-side anticheat required at all, which would be nice.