Surround sound doesn't necessarily mean more speakers, it's having the right speakers in the correct location.  Right now you have 5.2.1 (L/C/R in the Arc, 2 surrounds, 2 upfiring Atmos in the Arc, 1 Sub), which is the maximum for standard speakers in a Sonos Home Theater room.  The only thing you can add is another Sub.

If you have a large Living Room you might want to consider adding a second Sonos Sub. You could even swap-out the Ones for ‘Fives’ - but you can’t ‘bond’ any further speakers to the Home Theatre setup.
You can ‘group’ more Sonos speakers to the current setup, but that’s really only ideal for music audio playback, as all will play in perfect sync, but ‘grouping’ devices for TV audio can sometimes cause an ‘echo’ in the room due to buffering/delay in a grouped-room situation. 

That said, there are tools in the Sonos App, such as ‘TV dialog Sync’ and ‘Group Audio Delay’ that can sometimes bring the TV audio into line across a ‘group’ setup, but you may then notice some minor lip-sync issues with the video on screen… This does work quite well for my setup, but only when playing PCM stereo audio from the TV, but I don’t have much joy with lip-sync when playing any of the TV multi-channel surround-sound codecs.

Ok so move up to the 5’s since large living room and put in ceelling ones and be good then if want separate for music build around another arc or beam for music and and all around 

thanks for quick answers guys 

love the Sonos 

So is it best to get connect and if run roof speaker amp ? 

The CONNECT (no longer made) and its replacement the Port are designed for connecting to other Amps that drive speakers. All they do is provide the Sonos signal, and also act as an input device.

The CONNECT:AMP (no longer made) and its replacement the Sonos Amp include a built in amplifier to drive a pair of speakers without involving a separate amplifier. 

Care needs to be taken when purchasing used CONNECT and CONNECT:AMP devices, some are limited by the internal memory and can only run the S1 software. Unfortunately, it’s somewhat difficult to tell the difference, since there was no model change in either number or looks. 

So amplifier is good for in wall/ceeling soeakers then ? What’s the dedicated to help with WiFi issues called then ? 

If you don’t already have an amp powering those speakers, then a Sonos Amp is a great choice. 

I am afraid I don’t understand your second sentence. 

Is there a option to make delicated WiFi for the spears and system to hook to my internet 

Ah, you’re asking about the information in the wired and wireless modes FAQ. Wiring any Sonos device, with the exception of surround speakers, or the Sub, can create the SonosNet signal. If, like me, you have no device conveniently close to your router, a Sonos BOOST does the job quite well. Stay away from its predecessor, the BRIDGE, as it only can run S1 and frequently, at its age, runs into issues with the power supply fluctuating.

SonosNet is just another radio signal in your home, and all of the cautions listed in the wifi interference FAQ still pertain. It isn’t black magic that works as a silver bullet, but it is a great way to connect, as I have. 

Just curious what the Amp an in-ceilings would add to the already complete surround set in the room.