Degree, closeness, and betweenness all seem like poor choices to make such an important decision. Why not HITS?
MySpace is mostly erased (prominent Italian musicians for some music waves of the 00s and 10s were there), some sites are erased, what pertains to radio and television is mostly not indexed on the public internet and there's significant digital divide between genres. In the Italian context, you'd end with a weird pantheon of rock, rap and popstars and not much else left, in conclusion you would... expunge significant artists and whole genres from results.
However, degree sounds like a bad measure, since the value can be drastically increased by participating in a (few) big project(s).