Too many stops ?
The point is (I suppose) not to make too many stops in order not to spend too much money with landing and parking fees and in order to avoid as much as possible unfriendly airports.
Let's assume that a fuel stop in Sicily (flying with a PA-28) is necessary: I imagine that Trapani is at the first place followed by Catania and Palermo.
I'm quite sure that a PA-28 can make a trip from Salerno Pontecagnano to Trapani or Catania: this means that the last part of the trip is almost planned.
Moving north we have Pisa and also Perugia (which is not on the coast but might be a choice if you're planning to arrive from Switzerland instead of France.
Jude: give us some more details about your trip so that we can help you a little more.
CIAO !