[Long time lurker/first time poster. I hope it's OK to post links here. I still need moderator approval, so go ahead and delete the links if you must, but please leave the names so thy could still be searched on the web. I have no affiliation with hifiberry other than being a satisfied repeat customer.]
Hifiberry Digi+ Pro (
https://www.hifiberry.com/shop/boards/hifiberry-digi-pro/) provides isolated coaxial S/PDIF out and is perfect for feeding a modi multibit.
There's also the Hifiberry DAC+ Pro (
https://www.hifiberry.com/shop/boards/hifiberry-dac-pro/) which is RCA line out, perfect for feeding a magni
I highly recommend their steel cases for the Raspberry Pi + audio boards. They're a little tricky to assemble, but are nearly indestructible, and make a nice mechanical and electromagnetic shield for the Pi.
I also second the recommendation for Rune Audio, Easy to set up, easy to use, good online support/forums, actively developed, and I think it looks pretty too. It can be controlled by anything with a web browser (phone, tablet), or even a touch screen.
Unfortunately, I don't have any experience with Tidal/Spotify so I can't comment on those, but Rune can also function as a uPnP/DLNA endpoint renderer, which opens up the option of running the streaming services from a phone or PC and then render on the PI feeding your audio stack.