This is a difficult room for any equipment. I assume that the walls are plain. In an effort to somewhat control reverberation, I hope that there is some carpet with a thick pad.

I think that traditional L/R speakers in the front would be the best choice. For the rear speakers try not to place them too close to the sofa because the speaker nearest to the listener will dominate and the listener will need to carefully position at the “sweet spot”. A SONOS AMP would be OK for the front speakers.

A very contrarian approach would be Aminia speakers. These seemingly break rules, but they are thoughtfully designed and they will do a credible job in very difficult, live rooms such as this. Obviously, these will require some installation, but if this is an ongoing construction project they are actually not hard to install.

Thank you for the reply. The walls indeed are plain and there is a carpet between the TV and sofa.

I added a photo of the current setup. The plan is to replace that old 2.0 setup with a soundbar to get a tidier look. The wall behind the TV is concrete, so carving room for Aminia speakers doesn’t feel like a viable option but thankd! 
 

So far we have 4 different Sonos speakers in the apartment and I would like to stick with Sonos solution but will of course look elsewhere if that will provide a better solution. Do you think the upcoming Samsung Q950A might be a better compromise?

As you already have a number of Sonos speakers elsewhere in the apartment, I would try the Arc and Ones. Not sure which country you are in, but do you have Sonos’ option of a no quibble return? If so, why not try them and see what you think. With trueplay tuning and/or experimenting with the front/rear balance and rear speaker positioning you may well find it works OK.

I’m going to push on you a little. I understand that you think an ARC would be tidy compared to the current setup, yet you are tolerating the somewhat haphazard wire management to the TV.

You could try ARC and if the results are satisfactory, ignore me.

Thank you again. I wondered whether someone would notice the wires but yes, those will be hidden within a cable channel as well.

I think sonos Amp actually might fulfill my needs at least temporarily. It just feels a bit overpriced compared to Arc, even. Trying out Arc and going with Amp as a second option might be the way to go.