The Qb is stereo only (but then a very narrow almost single point source). And you cant use it within a surround system unless you use a home cinema amp and then utilise pre out signal for the centre speaker to feed to the Qb line in socket. Even then you would be sending a mono signal to a stereo line in.
I think you should look at simple home cinema set ups perhaps including packaged speakers. Richer Sounds have a yamaha amp + speakers incl sub for £329. It will get you surround in your lounge but it won’t be “top of the line”.
Next option would be something like a Sonos Beam soundbar @ £399, or the Playbase for £100 more. A sound bar is going to give you more surround effect, at least left/centre/right, which is what they are designed to do, and some can be partnered with a subwoofer for deeper thuds when Godzilla gets moving.
Obviously if you can stretch to the newest Naim Mu-so then you can take advantage of the hdmi connectivity but again with Naim it’s stereo only. But that would replace your Qb and beef up both your music listening and your tv sound substantially.