These are my personal regex blocks that I use in my pi-hole instance. I'm publicizing them in the event they may be useful for other people.
(\.|^)cn$
(\.|^)ru$
Regex list from mmotti/pihole-regex
^(.+[_.-])?adse?rv(er?|ice)?s?[0-9]*[_.-]
^(.+[_.-])?telemetry[_.-]
^adim(age|g)s?[0-9]*[_.-]
^adtrack(er|ing)?[0-9]*[_.-]
^advert(s|is(ing|ements?))?[0-9]*[_.-]
^aff(iliat(es?|ion))?[_.-]
^analytics?[_.-]
^banners?[_.-]
^beacons?[0-9]*[_.-]
^count(ers?)?[0-9]*[_.-]
^mads\.
^pixels?[-.]
^stat(s|istics)?[0-9]*[_.-]
^track(ing)?[0-9]*[_.-]
^ad([sxv]?[0-9]*|system)[_.-]([^.[:space:]]+\.){1,}|[_.-]ad([sxv]?[0-9]*|system)[_.-]
(ads|captive|logs)\.roku\.com$
(\.|^)meari\.com\.cn$
(\.|^)tuyacn\.com$
(\.|^)ty-us-storage[0-9]*[_.-]
(\.|^)merai\.com\.cn$
(\.|^)iot-dns\.com$
(\.|^)qq\.com$