Who are the fighters that can save boxing?

Outside of the heavyweight division and a few select American fighters, the fighters with the best chance at becoming "stars" are the ones with sizeable, dedicated fan bases...and most of those fan bases are based on nationality (Mexicans, Puerto Ricans, Filipinos, British, Irish, Russians/Ex Soveits/Eastern Europeans, etc.)

They're the ones that have reliable enough support already behind them that the people with the money are willing to put their money and support to promote them.