Hi toroistein
Option 1
To use the Bose 201's as front speakers you can connect them to a Sonos Amp and use a Sonos or 3rd party sub. A pair of Play 5's, Sonos Play 1's, or Sonos One's can be used as surrounds. Your TV can be connected to the Sonos AMP via HDMI_ARC or Optical if HDMI_ARC is not an option on your TV.
This option would produce a "Phantom" center channel for TV but natural Stereo for music. The rears can be set for ambient or Full stereo for music when not interpreting surround material. The switch would be automatic depending upon source (i.e. TV or Music).
IMO the Play 5's would be overkill as surrounds.
Option 2
You can use the Bose 201's as surrounds with a Sonos Amp while using the Playbar (connected to your TV via optical) and a Sonos Sub upfront. The Playbar would produce LF/C/RF channels which are best for movies. While music would sound good...you will not get the pure left/right stereo separation as with two dedicated speakers upfront.
Summary
While Option 1 is the most cost effective you'll have to decide for yourself which sound will be the most pleasing for Movies and Music (i.e. Option 1 or Option 2). Personally, I'd go with Option 1. ;)
Cheers!
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