My thought was to only use the new speakers for the turntable, keep the existing home theater for the TV. Those speakers have a matching sub available.
I haven’t really looked at Sonos at all.
I got the impression that you weren't overly impressed with your current setup. Can you temporarily move that tree to see if the sound improves? If it does, then we can come up with a work-around.
While vinyl is making a comeback, the audio differences between that and a decent quality digital recording is minimal and the added warmth is only obvious if you have a good quality system. That said, many people are blown away by vinyl because they are used to listening to compressed crap from the internet/Apple/Sirius etc. - and depending on your age, you might not be able to hear the differences between vinyl and good quality digital anyway.
I'm not trying to talk you out of vinyl, but with today's electronics, you'd need to be pretty serious about music to drop the cash for a system that sounds better than what you have now.