Yeah Bulgaria seems nice. Super low tax rate too - salaries are crap (even compared to Poland I imagine) but if you're self employed, would be a good deal.
I do wonder about it long term - population is plummeting. You could get a cheap place in some dying village I guess. Also, I wonder if it's going to become full of britfags who won't learn the language.
Speaking of learning the language, it's probably not a massive jump for you to pick up bulgarian.