CCRL only supports CPU (https://groups.google.com/g/lczero/c/_M6HNunemDw) and might not be meaningful for anything other than an MVP pre-GPU version of Pabi or a very slow & inefficient CPU NN adaptation.
CEGT seems outdated.
TCCC seems infeasible.
CCRL is still the most important rating list that is frequently updated.
Some of the most important championships & rating testing environments are
The major tournaments usually require 3000+ ELO.