1. There will be many opinions, some well formed, some not on ripped vs streaming, but having both, i almost never listen to my ripped CDs when there is likely a better sounding version on Tidal. Why better? Typically because they have re-mastered versions. I don’t find a big difference to most HD formats if the original recordings and masterings were excellent
2. I don know much about the McIintosh DAC
3. I also pretty much ignore the oddball format wars. Most music is RedBook - so i worry about where the music is. USB is a fine interface, if you take the proper precautions. Much to learn there- mostly about noise / ground isolation.
4. more on DSD and I’ll continue to say "who cares?"
5. Yada yada. You may think i don’t care about sound. Wrong -- believe me I care a LOT about sound quality, and have a crazy revealing system, but you are barking up the wrong tree worrying about all the niche steaming/digital formats. They really are not needed for great sound, and what does it matter since the music is not in those formats, unless you want to keep replaying the remastered version of "some nobody plays obscure songs, not very well". Pass.
6. Roon. Roon. Roon. I cannot imagine buying a last-century tech streaming appliance. I also dont want to pay for custom hardware. Nucleus is nice, but start by running it on an old computer. read up about how to get the best out of Roon. (the whole USB and network interface bit from above). Roon has its issue, but its also a great music-centric platform. I went from running it on a space 9 year old macbook pro, to building a dedicated ROCK server from an intel NUC. One key to good USB and roon sound is truly quiet, well isolated bridges. I custom build those from Raspberry Pis with custom power supplies and isolation. Not for everyone, but you can pay various firms to sell you the same thing.
Roon. Roon. Roon.
Now to really learn abotu streaming and the ins and outs i’d rather spend qutie a few hours watching this guy’s videos that asking random people here.
https://www.youtube.com/channel/UCR4tuhqPppVp-PD0q17sPEA
G