Recommendation for best sounding RAAT

I have a NUC with ROCK and a miniDSP SHD Studio as RAAT connected to my DAC via S/PDIF.

I would like to have the best possible sounding RAAT. Not many out there. Many streamers has all kind of features build in and I only need a roon endpoint.

There are SOtM SMS-200 and microrendu, what else?

Have a look at the very well-respected PI2AES Audio Shield. Some prefer it over high-dollar streamers as Roon bridge device.