You could upgrade CD player if you're going "analog in" top your pre/pro for 2 ch listening. Otherwise, going "digital-in" to your pre/pro is an option. That said, you'd overall have much better sound upgrading to the Classe SSP30 and matching amps for your B&W CDM speakers! That combination is stellar for the money, and isn't easily beaten. The Classe is a superior pre/pro to the Bryston sonically as well. The Bryston amps aren't better than the Classe's either.
If it were my money, you're upgrade path (without getting tricky) would be selling the amps and pre/pro , and buying Classe SSP25/30(probabaly 30) and maybe the multichannel Classe or Separates.
Good luck