14 Day Best of England Tour - any tips?

Yes, do arrive at least one or two days before the tour starts. Not only will it give you a chance to acclimate and get over any jet lag. it will also give you some elbow room in case of any flight delays. Have been to Bath at least twice on his tours, but don't remember what the tours included and what we did on our own. The RS site (or an email to the office) should give you that information. And there are plenty of things do see and do in Bath over and above what the tour does cover. Tea at The Pump Room was one thing we did on our own, as was a visit to the fashion musuem.

We loved tea at the Pump Room and lunch is also available if your travel partner doesn't want tea. When we were there, they had a chamber music ensemble playing-for me, live music really upgrades the ambience of the tea. I took the HOHO bus when I was there and it was a useful form of transportation. I really enjoyed the Georgian House Museum.

Cornwall is 1,375 square miles, you don't "do" Cornwall in a day. It's a large county that is not served well by public transport so a car is recommended. Driving can also be fairly slow due to a lot of single lane roads and quite often roads that are insufficient for cars to pass in opposite directions without needing to pull into a passing gap.

To fully appreciate Cornwall requires at least one week and the use of a car, anything less is not doing the county justice.

As others have said, Cornwall is not a day trip from Bath and deserves several days.

You might wish to read this thread which might be relevant to your query.
https://community.ricksteves.com/travel-forum/england/more-time-in-bath

I would suggest a day trip to Salisbury and Stonehenge, if you have not been to either before. Salisbury Cathedral is just gorgeous, and well worth a visit. And if course, Stonehenge is the iconic sight to see in England.

It's an easy train ride from Salisbury or you could rent a car or sign up for a day tour.

IF you've got extra days, by all means go early. If you want to see Salisbury and Stonehenge as Mardee suggests, You might consider taking the train from London to Salisbury and spending 2 nights there. ON the full day you can take the Stonehenge Shuttle from either the railway station or city center out to the stones, then stop at Old Sarum on the way back where the shuttle pauses. You can also time it so you can go to Evensong at the Salisbury Cathedral plus walk around the Cathedral Close, see a museum, enjoy yourself. THEN head by train to Bath (just an hour or so) a day or 2 before your tour starts!

I love Bath and always find enough to spend 4-5 nights there. There is a lot to see that you won't see on the tour.

I'd say no to Cornwall too...too far, too big.

This is an excellent tour, by the way! I had a great time on it and saw so much.

Yes to arriving in Bath at least one or two days before the tour starts!

There's lots to do there. Your tour will include:
A walking tour of Bath, including a walk up to the Royal Crescent.
This walk includes a walk past Bath Abbey, with your guide telling you the history, but not taking you inside.
The Roman Baths.

In your free time before the tour begins, you could go inside Bath Abbey and have a look. The day we were there, a men's choir from Wales was there, giving a wonderful concert.

We went on the sightseeing bus around town--there are two routes--we did both and enjoyed it.
One route goes to the top of the hills outside Bath, where you can get off at the American Museum, spend an hour, then be picked up again by the bus.

Other things to do in your first day or two in Bath include the Holburne Museum, with a wonderful art collection.
Bath is a great town for just going on walks and admiring the architecture.
Great selection of restaurants.
This is a great tour....you're going to have a wonderful time!

P.S. Forget Cornwall for this trip. Do think about signing up for Rick Steves Southern England tour, which takes you to Cornwall, among many other great places.