Speaking of things I like, I'm really digging Agatha's Christie's Poirot originally from the BBC. I originally watch the first couple seasons of this when they were shown on PBS in the early 90s. However, I just couldn't get into them and dropped out. Now upon watching them again I see they are just little gems with great characterizations, locations and attention to detail. They also do something that's hard to pull off: they go far from the words of the books and yet more than keep the spirit.
David Suchot pulled off the incredible feat of performing as Hercule Poirot in adaptions of all 70 Christie short stories and novels. The includes the final Poirot book that published during her life. The book Curtain, however had actually been written 30 years earlier. She originally planned to have it published posthumously as her detective's swansong. She changed her mind and released it a year before she died.
Another reason this show is so good is the budget was always kept at a solid level and that they are only making on average only six episodes a year. A reason why Columbo is so good compared to so much episodic television is it began as a rotation show on NBC's Mystery Movie. Unlike equivalent shows of the time like I Spy and Mission Impossible which cranked out at least 26 one-hour shows a season, Columbo only averaged six 90-minutes shows.