The Surprisingly Awesome podcast seems to have done a bit of what you're looking for while it existed. Some episodes more successful than others, but that's a strict topic podcast, with a strict release schedule for you.
https://www.gimletmedia.com/surprisingly-awesome
You should be able to find audience reaction to the podcast and it's cancellation if you dig around a bit on reddit. Learn from their work and make yours better.
Also, 99% Invisible would be another podcast to research to ensure you are barking up a different tree