Is there a way to keep all of my playlist radios from being the same?

[iluvcheesecake]

I like making playlists with a certain vibe and then using Playlist Radio when I'm in the mood to listen to that type of music. This worked great at first, but the Playlist Radios for most of my playlists have converged and all sound the same now, i.e. regardless of which playlist I'm doing Radio for, I'll hear the same songs. I assume this is because Spotify tries to figure out what kind of music you like and play that on Radio, but it's having an unintended effect. Maybe the genres of my playlists aren't as distinct as I think they are, but the artists in each of these playlists generally have no overlap even in similar artists, and like I said it worked great when I first started using Spotify this way.

The new "Hide Song" feature isn't useful for fixing this problem (at least as far as I understand) since it prevents it from being played anywhere by Radio. It would be much more helpful to have a thumbs-up/thumbs-down system that lets you individually tailor what songs/types of songs play more or less frequently on a Playlist Radio (similar to the old way, although I don't know if that worked exactly the way I'm thinking). Lacking this feature, is there any way I can reverse whatever effect has happened that's made all of my Playlist Radios start sounding the same?