Velo62 blams your B&W 800Ns for the grainy & weak bass, Although, I don't remember you complaining about weak bass. I have B&W 801Ns and I have never experienced weak bass. Notwithstanding, I suspect it is the synergy between your components that is causing your complaints.
I originally had the 801Ns coupled with a Parasound Halo C2 (which I still use for HT)& a Mac MC402. Perhaps, a bit bright but never grainy. This was corrected by changing my speaker cables to PS Audio Biwire Xtreme Statements. I have found that my 801s like copper in the mix. The mid and upper range further improved with the addition of a Mac C2200. The addition of a Hydra 8 made it near perfect for me. I have also done some tweaking with power cords. After trying several, I now have a mix of the Shunyata Anaconda Helix, Nordost Valhalla & Vishnu and Electraglide Epiphany X & Epiphany.
For wires that work best for your system, I would suggest, The Cable Company 1 800 FAT-WYRE. They are very helpful and have a "lending library." You can actually try several for the cost of mailing, which I believe is credited to a purchase, if you decide to purchase.
As far as an SACD player, I can't help. I use the Krell SACD Standard. I am very happy with it but it does not have tubes nor a volumn control. I have found that you can get many of the tube benefits from a good tube pre-amp in the system and still maintain much of the benefits of solid state. I have heard many good things about the CARY 306 but have not had the opportunity to audition it.
I hope you find something in my journey useful. Enjoy the trip and treasure the good sounds, Bill