It really is horribly slow now - and not just in the way that you describe. Previously, I could load the podcasts app, and tap the top item in the unplayed list, and it would begin playing the entire list. Now there isn't a way to do that. Instead that tap opens the list of podcasts for that show, and then I have to tap the podcast again to select it, and once again to play it. And it only plays podcasts for that show! As far as I can tell there isn't a way to play all of the unplayed episodes I am subscribed to.

I moved to Overcast.