I've happily paid for dropbox for years. I have always had one harddrive be my dropbox folder. that way if the OS went down, the files were fine and didn't need to be redownloaded. This is a critical feature to me and I have no interest in remaining a customer if this is not possible. I use Linux and Windows and Android. Several of my work flows require the classic rsync like features and custom location of Dropbox. Maybe I'm just missing it but I don't see a way to move my folder.
Also the app keeps soft pushing me to choose cloud only storage. Stop that. It's fine for some people if they want it. I will never want that because dropbox is backing up MY local files to your service. I am not using your service to get my files. Please pass this on to whomever is making the marketing decisions. I want selective sync of local drives across devices from where ever I wish to store the data on my machine.