I have exactly that wood combo on my tele. It sounds big and fat - more fatness than brightness, but there's still clarity, even with the somewhat mushy P90 I have in the neck position. Of course mine is also a Warmoth boatneck contour, which is physically fat (1" thick), so that contributes to the fat sound. I like the combo. The Goncolo Alves I'd say is more like mahogany than anything else, while the ebony keeps things clear. Because of the Gonc's density, you can play the whole neck raw as well (no finish), which feels smooth and fast.
In my experience, the neck material determines the sound more than the fingerboard material (a matter of mass really), much like the body contributes more to the sound than a veneer top on the body does. Both play a role, but the one with more mass contributes more to the tone.