Sicily to Naples advice needed

I know nothing about ferries between Sicily and mainland Italy beyond the short hop across the Straits of Messina.

I took an overnight train from Rome to Catania back in 2015. That night in a couchette car was totally sleepless and utterly miserable. I can't comment on the scenery because it was dark for most of the trip. You can check the train schedule and fares on trenitalia.com. If you're planing well in advance, the train ticket needn't be expensive; I'm not sure it would be expensive even if you got the ticket at the last minute. It would certainly be a long trip.

On the trenitalia website your origin will be Palermo Centrale; your destination, Napoli Centrale if you decide to go all the way to Naples. If you're considering making your next stop after Sicily ithe Amalfi Coast, Salerno might be the place to get off the train from Sicily--but I'm not knowledgeable about travel in that part of Italy.

I'd go to skyscanner.com for airline schedules. If you decide to fly, buy your tickets from the airline. Don't forget the extremely low carry-on baggage size and weight limits imposed by many airlines and their high checked-bag fees. The total cost of flying can be much higher than the ticket cost. However, in this situation, because of the apparent dearth of good alternatives, I'd either fly or develop a burning desire to spend a day ot rwo sightseeing somewhere along the way so I could break up the long rail journey.

A few days ago, I booked the day train (12 hour ride) from Rome to Palermo for my wife and me. We will be traveling in mid-Sept. The cost was 32.90€ each (2nd class). https://italiatren.com/en I assume going to or from Naples would be a little less. Booking ahead saves money.

I look forward to finding out what the experience is like.

Since you are going to the Amalfi Coast, what happened to the Grimaldi Lines ferries departing from Palermo to Salerno at 20:00? Thee are ferries and buses from Salerno to villages and you'd avoid backtracking south from Naples.

The direct IC train from Palermo to Salerno takes a little less than 9 hours and costs, on the day, 60 € per person.
If you could get tickets in advance and your plans are set, the Economy tickets cost € 29 whereas the SuperEconomy only € 22.9.

Not bad, but it's too much vacation time wasted on a day train. I'd rather pay more and take the night IC train departing from Palermo at 20:25.

Avoid re-sellers like the one linked above. You have no way to know they are showing the full schedules and all the fares. Or that they are selling real tickets, I have never heard about this "italiatrain" site. ItaliaRail is a reputable US based agency if you prefer not to use Italian city names and the 24 h. clock.

Thank you Dario!
I had read about an overnight ferry from Palermo to Salerno! But, everything I could see mentioning it was from years ago & I had trouble tracking down a direct link to the Grimaldi Ferry Line! I have found their website now and I see that they have an overnight trip for that route on Sunday nights!

I like not wasting a day on travel and I love not back tracking!

I thank those of you who answered me for taking the time to help me!
If anyone else has advice, I am always open to ideas from those who have gone before me!