Opie and the Spoiled Kid is great. "Oh. Well, don't get your clothes dirty." Andy and Opie's line deliveries are pitch perfect in that scene.
I liked that a lot of the color episodes focused on Aunt Bee, but I felt sorry for her. Her she is trying to grow and experience new things and Andy is constantly yelling at her and telling her she's not capable (or worse not allowed) to do things. He just downright awful to her most of the time. I mean come on, Opie was getting older, Andy was getting serious with Helen, Aunt Bee's friends weren't that great (Clara was a straight up bitch) and couldn't let her get some fulfillment in her life.
Of course the color era had some of the worst episodes. Howard moving to the Caribbean (WTF? Who in the writer's room thought that was a good idea?). Harold and Millie getting married (that whole thing had a creepy quality). Andy buying the laundromat. Anything with Warren.