"But apart from better sanitation and medicine and education and irrigation and public health and roads and a freshwater system and baths and public order... what have the Romans done for us?"

u/Tiako has, over on r/badhistory, analysed the claims of that one scene from Life of Brian, which deals with some of your questions (if, indeed, they aren't inspired by that scene in the first place). More can always be said from anyone who can contribute, so if you'd like to give it a go, please do!