:Yeah, the situation with the etymology of Byzas is complicated because I can't locate the sources I need, and as you said given the state of the evidence, a definite answer may not be possible. I want to find out the attestations of the name and its accepted variants (Byzas, Byzes, etc.) and see whether the *bhugo- (goat, ram) etymology has any evidence for it. Other etymologies I'm looking into is whether any sources have made a connection between the Illyrian Parthini and the Persian Parthians, and Partha was also another name for Sanskrit Arjuna, whose name means "bright"; did Partha also mean "bright" I wonder, because I've seen literature discussing whether the Illyrian Parthini and Parthenon may not derive from a Thracic or Illyrian word for "white" or "bright": Parth-, similar to Albanian bardhe.   

Afghan name