I went through this years ago and understand your concerns with the Oppo. The Schiit Bifrost is a popular dac and retails for around $800- there are others out there as well. I cannot recommend Topping.
If you go DNLA with your Oppo you can pick up a solid state usb drive for a good price, transfer your music files to it and use your IPad with the Oppo media control app to browse your files and control playback (no need for TV display). It’s kind of antiquated now but it will work until you make your decisions on other gear.
Personally I would lean towards a device that allows you to rip your music to an internal drive (as mentioned above) and that handles D/A conversion as well. Keep your Oppo for playing movies-