What I can't fathom from this thread is what you personally are thinking of doing, OP?
Do you want to rent, or buy? Or live in a city or a town or a small town or a village or in the middle of nowhere? Do you need to have a job there or do you intend to quit your job and HE and do you have enough other salary/partner to do this? Where do your parents and sister live and do you want to live within travelling distance of that place, and how far?
I can't get a handle on your proposed move at all, just some vague fantasy stuff.
A couple of million people live in Devon and Cornwall, and their experiences of live will differ hugely according to the above, as yours would depending on the above.
I think there are some constants-rentals are hard to come by, it rains in both counties, there aren't many jobs for young people, it's nice on beaches, but beyond that, surely it will depend on things like if you need a job yourself and if it's as a teacher, that will set what you do all day and how far you have to travel!
There isn't a generic SW life, because it depends on concrete things like money, finances, jobs, your lifestyle and any other parameters!