My next step is to run the Pi in headless mode so I do not have to have it connected to the mac and I can use the Pi's own psu for this I need an ethernet to usb adapter apparently?
Which PI do you have? I have the RPi 3, and they have several usb ports and also an ethernet port. I have various powersupplies hanging around, the IFI 5v powersupply is one, but also the Allo PS which came with my Allo Digione Streamer. Both the iFi and Allo ones are good. You can perfectly use a random phone charger, but this might cause hums / noise. A powerbank will work also nicely for a few hours.
I only use Pi's headless. The trick is to load an image on an SD card of e.g. Raspbian, and then put a file 'ssh' in the root. No fileextension. This will allow the Pi to be connected by SSH. I do have an unix background (did Oracle installs for a few years), so I have a headstart there. This could be different for the most people.
I'm not using Tidal, but Spotify. Raspotify works seamless, and I can also use volume control from my phone. Trick is to set
mixer_type "software" instead of
in the file mpd.conf. Raspotify is a package to be installed on the RPi which allows the normal Spotify client to stream to is using all functions. There is a tutorial on the Spotify site.
Next to Raspotify, I use HIFI Cast to stream my music which is stored on my Synology Nas using Minimserver. This is also a flawless and seamless integration. No issues, no restarts. Just perfect.
All I miss now is to use the Naim volume control. It is digital currently on the Streamer.
When I have a decent Dac, I'll set the streamer / dac to fixed output and will use my Naits remote control.
You are totally right on your observation that SQ is good but convenience might be a step back. Its a bit finding your own way. In my case, I like it. I'm thinking on writing software myself to control all the digital devices.