@King:
The problem with Rebecca right now is that she has less hype than Cavendish and somebody we weren't even introduced to yet. Rebecca got some praise from local fodder, but Cavendish and Bartolomeo were specifically hyped by a named character.
I mean, only 4 people may advance. Burgess already did. Luffy Lucyobviously will. That leaves Cavendish, Bartolomeo and Rebecca for 2 spots, and Rebecca is the only one there who could still stay relevant to the plot even if defeated because she seems to be in friendly terms with Luffy Lucy. Cavendish is already hostile and the other guy is said to be crazy.
I think Cavendish and Rebecca will advance.
Here's the thing, yes, Cavendish is more renowned than Rebecca, and it seems this "Bartolomeo" is too. However, Rebecca has quite a bit of mystery surrounding her.
I mean… I'll bet anything she knows Kyros somehow (could be his daughter), she is apparently undefeated (the "Undefeated Woman"), she...talks weird, well...when she was finished talking to Luffy that is, and lastly, she has something against Doflamingo, enough to want to kill him.
I suppose we have to wait for Bartolomeo, but right now, I'm placing my bets on Burgess, Cavendish, Luffy, and Rebecca being the final 4. She has an important air of mystery surrounding her.