I recently had a very rewarding experience in the "English Riviera" (in south Devon) in late February that might offer some of the things you're looking for. It was quiet and pleasantly uncrowded in the off-season, but most things were still open and there was plenty to do. Two of the main towns - Torquay and Paignton - have National Rail stations, and there's frequent bus service (as in every 10 minutes in some cases) to some of the smaller towns and more rural areas.
It's a heavily touristed area in general, but again, less so in the winter, and it seemed like American tourists were almost unheard of: Almost everyone we met, upon hearing our accents and where we were from, asked "So what are you doing here?" That opened the door to some great conversations - the proprietor at our B&B telling us all about his trip to San Francisco, a waitress who served us dinner talking about why she lives in small-town England rather than London, and a couple of people asking us what we thought of Donald Trump. Hardly the beginnings of lifelong friendships, but still, some great conversations.
There are plenty of places to hike, both along the coast and inland, with beautiful scenery. The weather in February is fine for being outside (or maybe we were just lucky), as long as you have a sweater, a raincoat, and good shoes.