> I've been thinking for a while that the podcasting business is ripe for disruption in terms for revenue models.

Don't worry, your widely known ideas for making podcasts bad have already been considered and implemented.

> Perhaps I'm not aware and these models have been tried already?

Yes. The former is DI / DAI through podcasting platforms (rather than the more artisanal and self-hosed podcasts, whether it's baked-in or DI). The latter is subscription platforms like Acast Access, Spotify (which bought several podcasting studios like Gimlet and Parcast) or Luminary, or "premium podcasts" features (with either subs or one-off buys).