It would be nice to have a new French destination so fingers crossed!
Also Cardiff to Naples is Skyscanner's Unserved Route of the Week with 20,000 annual searches.
Next Italian destination for Flybe maybe? Or would even TUI consider a weekly service? Other options from the Naples end would be Easyjet it's biggest carrier or Ryanair it's second biggest carrier.
http://www.anna.aero/2017/12/13/car....4876a-86828221