Sorrento as a base for Amalfi Coast and area?

The best way to get a sense of this is to read through previous posts (it is a very common question). Some people like to unpack once, other people like to experience evenings in a place and avoid long day trips. Positano cannot be any more touristy than anywhere else on the coast--it is very famous and popular.
It also helps to know what you are going before and after. If you are flying out of Naples at an early hour, for example.
Please also look at beach pics online, as it can be surprising what the beaches are actually like.

Be sure to look at some of the links to old discussions in this thread:

https://community.ricksteves.com/travel-forum/italy/salerno-or-sorrento-for-6-nights

We spent a few short hours in Positano, that was more than enough for us. It’s tiny, steep, crowded with tourists and high end shopping.
YMMV
With just 5 nights I’d stay in Sorrento and day trip to Pompeii, Capri and Amalfi
I don’t think Ravello is well suited as a base, transportation is iffy and it sits high up on cliffs, no beach there.

Take a look at the tours offered by Mondo guides-RS recommended
They have a small group affordable day trip along Amalfi coast that gets you to Positano, Amalfi and Ravello
We enjoyed their day trip to Capri immensely, also used for Pompeii
www.sharedtours.com

I stayed in Sorrento pre-pandemic and found it an excellent base for exploring the area. The town itself is sort of a postwar destination and not particularly historic but it's got beautiful views and is well-connected to Naples and Pompeii for day trips as well as Capri by ferry. Also a decent grocery store for making your own picnics etc. We took a Mondo tour of the Amalfi Coast and were very satisfied with that. In terms of beaches, you may need to adjust your expectations ;)
Have fun,
Cynthia

We went to Sorrento in late September and stayed in Sorrento (pre pandemic). It was fabulous, less crowds and not too hot. From there, we were able to easily travel to Pompeii, Capri and the Almafi coast (take the citi sight seeing bus to there, not the public transportation). We stayed at the Hotel Plaza, which was much more than we usually spend, Sorrento is a destination for Italians and Germans and we personally saw a wedding or two every day we were there. Hotel Plaza was worth every cent, the bedding and mattress were so comfortable, the windows were double paned (you are close to the center so it can be noisy) and very close to the train, buses and center of town. The fruit market was directly across the street beside a restaurant that had a service window with pizza that was out of this world delicious.

I stayed in Sorrento when I visited the coast and it’s a perfect base if going to Pompeii, Naples, Positano, Amalfi, Ravello and Capri. Did I like Sorrento, I was a bit disappointed but did partake in the early evening passeggiata.