Download by Playlist order
This suggestion is a method iaantended primarily to help users with storage restrictions (but not necessarily) and could be implemented as an extra option inside playlist.
The user should be able to set episodes download cache limited by MB or by time, for instance, 500 MB or 5 hours.
And instead of select episodes to listen by downloading it (like it works now) we would select them by just queue in the playlist, putting at the end of the list by default but a long touch would allow to queue as next (the 2nd) or play now (the 1st).
Lets suppose there is a total of 12 h 35 min of play time of all queued episodes ordered in the playlist and the 6th in the list reaches one of those limits set so until this episode will be kept locally downloaded using storage space and as they are being listened and cleaned the 7th (that now became the 6th) will be downloaded and if theres still space or time remaining the following are also downloaded.
MB limit would require the option "Automatic Cleanup > Once listened to".
Having a locker icon in the playlist screen to prevent inadverted sortings would also be an interesting improvement.
I understand this would represent a great improvement that besides helps us with have better control on storage usage it also will let us queue lots of interesting episodes from different podcasts, such thing isn't possible today unless we download every each episode sacrificing our device storage or we need to remember to go back in each of the several podcasts and select each of the several episodes we still want to listen as we advance on listening what we already have downloaded.