You mentioned Purple Heart. I too was looking for something similar for one of my builds, and decided on Camatillo. It's not nearly as well known, but it has purple hues. I think it has less contrast, blends better and is more "woody" than purpleheart...
As for rosettes, perhaps your luthier might have a style or other rosettes that they've done? If it were me, I would try to work around those parameters and wouldn't do a stained glass rosette unless it was Jason Kostal doing it (that's just me though). There are so many cool and original rosettes out there that I would try for something original, yet something that would blend well with whatever else you have going on.
BTW, welcome to the Forum!