I am not really into shipping but it has to be pointed that that those two are Hancock's male counterparts. Cavendish is considered very beautiful and thinks he can behave however he wants due to that. Barto is the biggest male Luffy fan, Hancock is the biggest female Luffy fan. Should Luffy continue to reject her as romantic partner (though he will accept her as nakama soon!), she should end up with one of them.