Personally I do think it makes sense to read them in order, at least most of them, as there are so many characters introduced in particular books who are brought back later on and built on. But all read not in one sequence with no other books in between!
Equal Rites certainly was one of the weaker stories, and Wyrd Sisters wasn't great which was why I was surprised when a cartoon series was made of it. There was definitely a lot of improvement in the stories after the first 3 books though Colour of Magic did set the imaginitive stage very well. Otherwise other than a couple of the later books I think they were generally brilliant. Guards Guards seems almost universally to be a favourite. What a book! The City Guard stories always worked really well with tales like Feet of Clay and Men at Arms.
