I just want to suggest trying other speaker cabinets to see how they might affect the tone of your setup.
I was amazed how much the tone of my old Fender Bassman 50 improved when I replaced the speakers with new Jensen P-15s. It's a much deeper, more woody sound. And there seems to be the same deeper tone even when I swap the Fender head for my Acoustic 150b head, which is not a tube amp.