And Aragonese or Asturian are not more different from castilian as andalusian, they were it in the past, but not today.
That's not true. First of all, Aragonose and Asturian are not dialects from spanish, they derive directly from latin. The Asturian has also a special status in Asturias, and is official in Miranda do Douro with the name of mirandés. In Leon, where it's also spoken (with the name of leonés) has no special protection. You should read more about this before saying things like that...
The difference with the Andalusian is that it is a dialect from Spanish.