Raspberry Pi4 Streamer - USB output?

First to run the Pi as a streamer you need to have Logitech Media Server loaded . PiCoreplayer can do this Moode only acts as a player . I would also strongly advise that on LMS you use the plug Material Skin for your GUI it is really a much nicer to use and look at skin .

With the Pi 4 they separated the USB and the lan controls and so the USB function directly from the Pi 4 is much quieter and yes it will work well in to your DAC directly . If you find a cheap one then a GD Audio USB convertor will improve the sound and allow you to connect to the DAC via SPDIF which in my view sounds better .

An improvement for your Pi would be a good 5 V LPSU needs to output 3 Amp but just makes things better . This can wait and if you want to borrow a PSU to try get in touch as I always have spares knocking around which you are welcome to trial .

USB cables is indeed a bit of an area you can pay very large amounts and others swear they are a huge improvement . In my view and following advice given on here Supra basic cable is very good and can be had new for under £50 and is worth paying for . The Excalibur which is the one up from the basic is an improvement again but only you will know if the additional cost is worth it .

I know that Moode has a basic server you can use but I would advise using LMS as it is a fully developed server software and has what they call plugins for things like , Spotify , Qobuz , Tidal , Deezer , Radio Paradise , BBC Sounds and others which makes accessing these really simple . Let me know if you need anything further .

I have a couple of spare Supra Excalibur, I'd be happy to let go for the same price (delivered)as a basic Supra 2.0.
Anyone interested just PM me.