I do exactly what you're proposing. It sounds really great. I've been investigating other streamers to upgrade to but the Node 2i seems really good.
The coaxial digital output sounded better than the optical in my system.
The Node 2i does the first unfold of MQA files on Tidal, if you set it to do that. Your DAC can do the final stage of rendering if it's MQA compatible, or just decode what the Bluesound sends it.
I did a lot of cable demos to see if the sound could improve and succeeded with rather inexpensive options, even after demoing a number of high priced and well reviewed digital coax and power cables.
Also, I found the difference between wifi and ethernet negligible or non-existent in terms of quality of sound. That said, I did hear modest differences when demoing different ethernet cables. Perhaps my network setup minimizes differences with regard to wifi/ethernet and the effects on sound quality. I'm currently using ethernet because I have easy access to do so and the wifi connection of my Node 2i isn't great, even though it should be 100% - for whatever reason, it doesn't receive a strong signal. It seems like a fault of the Node 2i. But don't write off wifi until you try it in your system.
