Hi again
I am confused as to which 2 rooms you want music in. The sonos product you mention (s5) is similar in concept to the sb boom an amplified speaker with wireless streaming. The zp120 is a streaming device with an amp which requires speakers attached, this in the living room isn't a particularly hifi solution...
Sonos and squeezebox duet are 2 ways of achieving the same end - a nice hand held controller to browse all your tunes and stream them wirelessly to a stereo or to their own amplified speakers. The main difference is that current squeezebox products need a pc running to manage the software, whereas the sonos product has this built in (although the new squeezebox touch also has the software built in) and this allows them to run from a simple nas drive.
To complicate this slightly the current squeezebox products can run from a powerful (and more expensive!) nas drive but setting this up is not for those without good IT and home network savvy. This is how I run mine and the setup was a pain in the hole, although it runs flawlessly and has done for 18 months now...
The sonos is considerably more expensive than the squeezebox, but sound quality wise I do not think an enormous step up, esp. if using the zp120.
Personally I recommend the sb duet for the main room, the boom you already have for your kitchen and another for the bedroom, cost £230 duet and £176 for the boom. The duet controller can also control both booms.
Alternative is zp90, controller and two s5's which would come to £1150, which is a lot more for the benefit of not needing to have the computer on, or a zp120 for £100 more.
The rest you can use on a decent stereo. Bear in mind that once all the cd's are ripped a good cd player is pretty pointless, which is why I would suggest the avi adm9.1s. Although at £1150 a pair they may be a bit OTT? I would highly recommend spending the bulk of the budget on the main listening room though. Cheaper active speakers exist which may be ideal with either sonos or squeezebox.
Alternatively the marantz pm6003 amp and cd6003 and wharfedale 10.1 combo at £600 is very reasonable and gives you an immediately playable system, while your partner rips all those cd's.
For £1k I would get the sb duet and marantz combo and another boom and save up for a good nas system to run it all, using the computer in the meantime.
Or for £1250 get the sonos zp120/cr200/s5/s5 system and a pair of wharfedale 10.1's (£200) and any decent nas (£100 - 200) to store your tunes. Total £1550 -1650. Personally I don't think this is as good as the above squeezebox and marantz combo.
Either way your partner will be absolutley thrilled...