That one was probably my favorite too.
Legion World is too big. You don't get a sense of any place in particular. And they don't seem to have a meeting room - you either see them in some sort of auditorium (the election of Kid Q) or standing around (when RJ announced his mission to the Kwai). The Weisinger Plaza meeting room was corny cool. They even had birthday parties there.
I also liked the old whore-house planetoid they used in the TMK stories - the way it was broken down and decrepit.