I had been toying with an idea like this last year. Basing a module on a map of Waterdeep, or maybe Zhentil Keep. I was put onto the idea mostly by the work of those fans who crafted a module based on Palanthus from the DL setting. Of course, you have to have time to work on this project, and that's something I have little of at the moment...so many other 'projects on the boil'...