The gen 1 streamers can have functionality extended via low cost add ons like an Ifi Zen Stream to the digital inputs. But I think that only makes sense if you already have one you are happy with and want to extend the functionality. Buying a new (to you) one that will need add ons to grant it new lossless or hi res online streaming seems counterintuitive.
I would hold on till something that does everything you want in one box comes along… or break the link and go the separate DAC and transport route.
If you like the Rega DAC sound (as I do), then how about just buying another Rega DAC, or even better, a DAC-R? They do come up from time to time on the well known auction site. That way, it’s just the cheap(ish) Wiim streamer that will become redundant as streaming tech moves on, and the streaming transport can be swapped out as needed.
Love it, not many Dac’s I have heard are that coherent, admittedly its not the most detailed transparent Dac out there, its just damn “musical” - should have kept my old silver first edition Rega Dac too for this occasion. but no worries, they are quite affordable s/h.
Not sure there’s more diff than usb in /R vs non /R ? Maybe less filter options.
If you use Spotify (as my family does) the difference between lossless and the ‘regular’ is significant. You cannot play lossless on the ND5XS. I got rid of mine for this reason.