As we have a 2 year old, we have to break the journey up with a couple of nights on the way down, Drove to Gloucester and charged at a BP Pulse early doors before the wife and little 'un woke up, really nice location next to a restored canal. The next night we stayed in Bude & there's a GeniePoint in the main car park there.
Whilst in Polperro we'd use the GeniePoint in Looe to top up and when we stayed in Penzance for a night there was a Swarco charger right opposite the Premier Inn we stayed in.
On the way back we used an Ionity (had to wait a while) and then an EcoTricity charger to get us home in one go.
TBH we found the public charging experience very easy to live with, my car is averaging 2.8/mpKWh since collection (4k miles in last 3 months) and is showing a total (at 100% of around 230 miles) and we've found that quite accurate, though I've only had the car whilst it's been quite warm, I expect this will drop well off in the colder weather.
Yes this is my first electric car, we're booked back in to Polperro again for next June already, although we will have another child with us again this time
I may take you up on that kind offer! We stopped for a couple of hours in Charlestown on the way back from the lost gardens, very close to you!