This raises the questions of which conferences have the most complexity theory in them (say by percent). Here is my rough guess.
- LICS has an occasional article on descriptive complexity)
- SODA has an occasional lower bound. The few SODA papers I've been asked to subreferee have all ended up being rejected. The very fact that I am being asked to subreferee is an indicator that they are out of scope.
- COLT/ALT and the other Learning Theory Conferences.