That sounds like a very nice cruise!
I agree on the 12 day cruise. You may also have some more sea days which is very good to have as you may need to rest as I guess it will be very long days in port (full day excursions in many of the ports, just to see as much as possible).
Oddly enough I have not been to Greece or Turkey yet. When I cruise in the Med it has always been the western part, as I love France and Italy. In October this year I will go to Cannes for the first time. Just planning on taking an independent walk there, or possibly join a 3 hours guided walking tour.
Florence and Rome are great cities to visit, but I'm sure you are well aware of the already. The leaning tower in Pisa is nice to visit, but in general I prefer Florence before Pisa. I think there are excursions where you visit both Pisa and Florence.
Naples is an interesting city - just look at how they park their cars! The cruise port is almost in the middle of the city. I did a stroll in Naples two years ago. The only thing to remember is to be careful with the traffic - it seemed cars wouldn't stop for people that were about to cross the road, but you have to look determined and take that first (careful) step out and then they stopped (but veeery close to you...

). This year I may take a tour to the Amalfi coast. Capri is a nice visit too as well as Pompei. So much to see there!
Radiance class is a favourite of mine but I have only cruised with one of the ships in that class - Jewel of the Seas. Have been onboard Radiance and Serenade during a day each though, but spent most of the time in the engine room.
/Erik
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