i think it would work better if eligible teams could search for available PLs as well, which has never been the case...
Yeah I was going to suggest this as well.
At it's most basic level, when setting up the PL you could have the option of making it public or private.
If set to public any team can view the league and apply, and then the PL owner can accept/decline each application (e.g to ensure team's are roughly similar ability).