Connect the two One SLs as surround speakers to your Playbar for your home theater setup. Set up the pair of Play:5s as a stereo pair in another room to use for music.

”Best” depends on what you want to achieve. There’s no Play:1 SL so let’s make some assumptions. If you want a 5.0 home theatre system, use the One SL’s for surrounds, bonded with the soundbar as a room configuration. Then if you can use the Play:5’s set up as a stereo pair for music duty in whatever room you want, or have them as a single speaker with each in separate rooms.  

Thanks