I believe part of the problem is the inability to just enter a team. If you take a look at Skunk's $120M Blacklist league, you can see who is unavailable at the conclusion of each season. This allows people to get right to the team center and begin working on their team.
It can often take a while to fill a "standard" theme league. While this is one of my favorite leagues, I think the current setup leads to additional delays and uncertainty.
At this point, virtually all cookies have been excluded, which was the primary intention. Perhaps going forward, you may consider borrowing from Skunk and just blacklisting the various league leaders at the conclusion of each season, and eliminating the owner-selection of blacklist players.
Anyway, that is my unsolicited two-cents. Fingers-crossed this league will continue to fill. Thanks, thurst63 and A51Man.