Aside from a nice digital "pinglike" taptone, a great piece of mahogany looks like it's put together in inch stripes...ribboned as yours is. Many luthiers use that as a sign that piece will be a great instrument wood. Beyond that, I've heard more than one respected luthier comment that excellent pieces of mahogany (and walnut) have an irridescence to them. By all accounts, it seems as though that piece of mahogany you have there is a fantastic tonewood. I'd like to hear what that bass sounds like!
Also, Unicorn bass is firmly on my radar of places I'd like to visit and potentially order from.