Nice hear from you again.

About Naples I'd recomend to walk around the city centre (I mean in Spaccanapoli and via S. Gregorio Armeno close the S. Lorenzo Maggiore church) because Dicember is the month of the traditional Christmas fair. It is not like others Christmas fairs in other cities, in this one artisans sell nativities scenes and statuettes with the face of actors, politicians, mainly Italian but also international, and so on.

About your itinerary, I thinks it is too much for short time.

In Matera, Sassi are worth a visit. Some years ago there was some university students waiting for visitors. If there are,

rent one of them to show you the area, it will be better for understanding.

Hope could be useful, Ciao, Marco in Milan - Italy