Thank you for your show!
I too use podget (I talked about it earlier - HPR1992). My podget saves nearly all files in folders named with date. You get this by setting %YY%-%MM%-%DD% after the feed-urls in your serverlist. This way you can listen chronologically and can easy delete all you listened to without the need to know it for every file. You didn't have to use cleanup-function of podget either.

Did you set MOST_RECENT=xx in your podgetrc? I set it to 30 and it works.

On the question of syncing between devices I recommend to use rsync. You can take a look at the script I wrote https://github.com/swegryps/bepackpod for inspiration.