For a second at the end I thought Chuck was setting Ryan up to announce that he was in fact doing a GL/Flash show

I would totally listen to that, but I can't imagine the work that would go into running two shows and doing the community around both justice.
I also hear the thing about the co-host. I did 6 or 7 episodes of a podcast by myself and then realized that I wasn't having fun without a co-host.. Not to mention all the pauses I had to edit out ha.
I think a JLA show would have appeal, taking format cues from Star Joes, covering the current team and working through the retros.