+1 for Castro. I can't believe more podcast apps haven't caught on to how handy the email-like metaphor is for managing episodes.
I want to listen to some, but not all episodes that come in via my various feeds, so having an "inbox" of sorts from which I can either download or discard shows seems like the only reasonable way to handle things IMHO. I don't understand apps that just download everything or, like Overcast, mess around with playlists.
I agree, although a lot of listeners do listen to every episode of every show they subscribe to. It's just a personal choice.
I still use Overcast, though, but mimic the Castro behavior to a certain extent by having a "Latest" playlist and a "Starred" playlist. I look at "Latest" every day, star the ones I want to listen to, then eventually play from Starred.
This works fine for me, but probably skews the shows' stats a bit since I download many more episodes than I ever listen to.