I run multiple rounds of DM, I keep it somewhat the same but change them specifically for the time of year. I keep them looking somewhat the same so that they are recognizeable. As far as other DM questions, do a search, everyweek someone starts a new thread, I'm sure any other questions you may have, have already been answered
Why do people not respect us as they do other tradesmen? Because every Tom, Dick, and Harry doesn't think he can be a plumber or electrician!