I agree with every thing above. Tavistock is one of the nicest towns I know but please stop telling people about it. Huge number of lovely villages throughout the area but be a bit careful a few are becoming dormitory villages. The whole area is invaded in August but dont moan about it as the income supports an awful lot of the residents, just go on holiday yourself.
I dont like cities anywhere so my comments would be badly biased. The plus is you dont have to go far to get out of them.
Negatives. Its more than a 2 mile drive to find supermarkets like you have.
Its wetter than MK
Strongly suggest renting and would do at least one in summer and another in winter. If Dartmoor is an attraction its beautiful but 2 coats colder in winter.
Good Luck