I use a Zu Ash digital cable and I like it a lot, but it cost more than the one you have. I think the Ash can be bettered, but not at the promo price I paid on eBay and probably not at list either. I agree that your front end justifies a better cable.
I have yet to test Audioengr (Steve Nugent)'s contention that 1.5m is better than 0.5m length, when it comes to digital. However I do feel I need to test it, since it appears to depend on poor transport design. I would like to think that is not a given.
I am using an Apogee DA-1000E-20 DAC with my Zu Ash cable. It has balanced outs and, with its power supply, goes for $400-$600 on eBay. I am quite happy with its impact and detail.
If you get the chance, let us know what changes you make, and the results.