That's pretty much the same setup i had with sky box, xbox and stuff in the lounge but my living room wasn't that big so I wanted to free up the space all the av kit was taking and then stick the tv on the wall, it did free up a lot of space and looked a bit more impressive!
I also wanted to see the sky box and stuff on other TVs in my house, that's when I realised it can be all be located in one place and controlled from each tv location, I confess I've ended up playing Xbox from my bedroom just because I can lol!
ive only got one sonos connect amp (all I can afford at minute) and that is in my cupboard wired up to two ceiling speakers in my kitchen/diner, works a treat and sounds amazing. If you add something called NAS (network attached storage) you can store all your music, pictures and video on it and you can get that streaming to all the TVs in your home too, I bought a western digital mybook live for ÂŁ100 two years ago and it's never let me down once.
as you can see it all become a bit of a hobby, I've probably still got the wiring diagrams I did if you want me to send them to you, I was operating on a budget but I was really surprised how simple it all was in the end and with the cable and everything I needed (excluding TVs) I think I spent about 600 quid overall in stages.
glad to help mate drop me a line if you need anything Inwish I did more of this stuff, was looking at becoming Cedia accredited and they estimate that smart homes are worth a billion quid annually in UK, I'd love to do a system which had the high end kit!