Steve, take a look at this thread: SonoreUPnP Bridge (beta) . By using this you’d keep the Melco ‘sound’, but use Roon as the front end. I know this solution is quite tweaky, but as far as I can see this is the only way you can combine Roon and Melco and (hopefully) get the best of both.
I am using a microRendu and a Mutec MC3+USB in front of my D250 Pro. Quite similar to what Brian (Confused) uses although he has gone ‘all out’ and bought the Mutec REF10 clock and various SOtM gear after he upgraded his D1000 to CI.