Do you have Sonos speakers elsewhere in the house? If so, I would suggest keeping the Sonos connect to integrate with the rest of the house when you need to - we still use Sonos to play Radio 2 in multiple rooms, synced, every weekend, including through the 2 rooms with Naim devices.
An NDX2 seems like the way to go in the streaming dept, but that’s a large chunk of your budget and doesn’t leave much for the pre-amp area, unless you go older and secondhand - an NDS with a secondhand 282? Again though, being the older streaming platform, I am not sure of the wi-fi capabilities of teh NDS