I play Stranded KOTH a lot and lately started trying TDM as well. It's enjoyable mainly because the teams constantly mix up and you don't get as many lopsided matches with full rooms. I think stranded should be an option for all playlists. You would select the gametype then choose between Ranked, QM, or Stranded (which would just follow QM settings). This would also free up 2 spots in the FoN section for more event playlists.
Could even add alpha or zeta options too.