Suggestions for Itinerary 2022

Looks like a fine plan to me. You generally want to avoid driving IN Naples, but picking up the car at the airport would be fine, as would picking up in Salerno.
Check on all of your train options and search car providers at Bari and Brindisi airports for drop-off. I found it only a small fee if any for dropping off at a different location within Italy.
What month will your trip take place? I would need to know where you will visit in Sicily and Calabria to recommend a place in Puglia (perhaps as a counterbalance, etc.), but I like the Itria Valley villages in Puglia, and I enjoyed Lecce as well. Are you looking for a town or rural stay, etc?

Messina itself isn't one of Sicily's highlights. Is there a reason why you want to go there?

Rail service between Puglia and Sicily is very slow. It looks like 7 hours from Taranto to Messina. Starting from a different origin could add considerable time (and train transfers). You'd cut your ground-transportation time if you visited Calabria between Puglia and Sicily, though I realize you may have a reason you need to be in Calabria at a specific time.

You didn't specify how much time you'll have for Sicily. It really takes at least two weeks for a good visit to its highlights with a car, and more time would be better. I had 17-18 days; using public transportation I had to omit some places I'd have liked to see, including the Aeolian Islands, and I didn't go to the Greek sites at Segesta, Selinunte or Agrigento for lack of interest. You could of course focus on just the east coast (Taormina/Catania/Siracusa) in less time than two weeks.

I'm just curious about why you are spending 7 days in Positano. It's quite scenic, but unless you're planning to use it as a base to see Capri, Sorrento, Amalfi, and some other places, there's not really enough to do there for more than a day or so.

Enjoy your trip, and have fun planning.

Hi aammiran -
I see from a previous post that you've been to Rome before so this isn't your first trip to The Boot. :O)

Regarding your 7-night stay in Positano, I don't see mention of the time of year you intend to take this trip? Along with not much to do there (it's not very big), it's also not an especially convenient location for day-tripping just anywhere in the region. For instance, it's sort of a pain to get to Pompeii from there (maybe you were intending to do that one on your way south from Naples?) and it only has ferry service from roughly April through October. Ferry service can also be cancelled if the sea is too rough, and there are no direct ferries from Naples. Buses can involve some wait time during high season.

Apologies if you already knew all this but thought I'd throw it out just in case you won't t be traveling during the warmer months (and even if you are.) It might be helpful to know what your plan is for spending those 7 days, and how much time you have for the entire trip? We haven't had the pleasure of Sicily yet but what I've picked up from RS posters who have is that it's a large island deserving of quality time to explore! And no, Messina isn't high on the list; other locations are reported to be more interesting.

I would suggest you purchase a Michelin Map of Italy and map out the logistics of where you want to go and for how long.
I have not been to Sicily but I would heed what posters are saying in the time you need to spend there. I would also think it wise to leave it for another trip as I know you will return to Italy like we all have on this site.
I would think the 4 days in Rome and taking a fast train to Naples, Circumvesuviana train from Naples Central station to Sorrento and then bus to Positano - I agree 7 days is maybe too much for Positano - consider 3 nights Sorrento, 3 in Positano and then 1 night in Salerno(bus) where you can pick up a car to drive into Calabria. You do NOT want a car on the Amalfi coast. We drove from Sorrento to Positano where we left the car for the duration of you 4 night stay in Positano.
I do not know where you have to go in Calabria and for how long but you could consider then driving around the arch of the boot into Puglia. If you have the time you might consider visiting Matera north of the arch before you get to Taranto.
If you take a look at the map you can better figure out where you want to navigate.
Hope this helps some.

Hi, thank you all for your insights, I should be more specific, we plan on going end of August into September. My destinations are Rome, Amalfi Coast, Puglia, Calabria and Sicily. We fly into Rome and planned on flying out of Lamezia, since we have family there to visit. I love to stay in Positano, but good point to stay in Sorrento too, I will also be staying overnight in Naples from Rome and then head to AC, I hope to visit Puglia (10 days) and Sicily 10 days and Calabria 4 nights. I would like to pick destinations along the coast and old towns to walk to but since we will have car in Puglia and Sicily we can drive to different areas. I think it makes sense to visit Calabria last since we plan on flying home from there.
Thanks again for everyone's advice

Until you are set on where in Sicily, it will be best to hold off on determining your order. You may find it better to fly if you wish to visit Puglia after Campania. Of course you can spend 10 days in Sicily, you will just have to be selective.

For Positano, the go-to resource is Nicki Positano (aka Nicole Storey), look for her on Youtube