Ravello gets universal rave reviews. But it has to be noted that it's at a higher elevation than the actual Amalfi Coast, and is a considerable bus or taxi ride from "civilization". In that sense, it might be described as a poor "base for daytrips". You didn't exactly say that's what you want, but I just wanted to make the observation. Amalfi is the point where the two bus routes between Salerno and Sorrento meet.
In the sense that Salerno is convenient to Paestum, while Caserta has the Palace, they are very different. I have not been to either of them. It seems possible to train from Salerno to Caserta, but probably with a change in Naples (?) Check Caserta as a daytrip from Naples? Sorrento is considered the busiest off-season town in the AC area, so you can expect some stores to be closed in October/November. I've only been there in the summer.
Bologna seems like an outlier, simply for distance, despite being a lovely place to stay.