Honestly, we were in exactly the same mindset as you when we attempted our staycation in Dorset. It soon falls apart.Travel to/from airports, check ins, getting absolutely nothing out of my currency, language etc. Just can't be bothered with the hassle of it all.
Firstly realised you can't go anywhere "nice" in the UK without a car. So we had to hire a car. Which cost a fortune. If you don't you'll be a stupidly expensive train (especially going southwest). Then, in the UK any hotels and B&B seem to run some sort of mafia-esque racket where it's impossible to find something decent for less than £75/night. What a joke.
Seriously, just go abroad.