To make your trip really simple and possibly more enjoyable, consider staying in Bath and taking a couple of tours with this company: Mad Max Tours. (Recommended by Rick Steves and mentioned in his guidebooks for England and London.) There are several tours to choose from. And you will not need to rent a car. https://www.madmaxtours.co.uk/
Tour is in a small minivan and pick up point is right behind Bath Abbey.
They do a tour (Tour Number 1) from Bath to Stonehenge that includes some Cotswold villages: https://www.madmaxtours.co.uk/tours/stonehenge-full-day-tour
Tour Number 2 is called Heart of the Cotswolds, and I would do this tour instead of renting a car: https://www.madmaxtours.co.uk/tours/cotswolds-tour
You will find that people here on the Forum are divided on the subject of renting a car in England. Some think it's a good idea, others never rent a car in England, thinking it's an unnecessary hassle.
My preference is to not rent a car, but to use trains, buses (coaches), and small van tours. But that's just my personal preference. The places you're talking about going are easy to do using trains, buses (coaches), taxis, and small van tours.
From Bath you would have an easy train back to London.
This way, you'd have one base (Bath), no need for a car, and the tours would take you everywhere you want to go. I'd do one Mad Max tour one day, then another a second day. This will keep you busy.
I realize you asked about touring with a car, but I wanted to offer an alternative.