Hi Mark. :thumbup:
Speaking from experience 😛 with the hotel being so close to the Circumvesuviana you can get into Sorrento very easily and then use the local transport. Positano the first stop on the Amalfi Drive is great, lots of steps though! Nice beach and lots of shopping.
I haven't spent a lot of time in Naples apart from getting down to the docks (as I told you in France/Belgium), BUT there is the Castle there and the Archeological Museum.
Also if you made your own way to Sorrento and made a day of it you could do your own thing and get across to Capri. I would defy anyone to get lost there and you would probably see a lot more than you would on the tour with no disrespect. 😃