After several hours of hacking through sitefinity, I've finally discovered a way to change the default upload folder for the file manager inside of the RadEditor for generic content and I would like to share my experience in case it might be helpful to anyone else.
Basically this allows you to change the default start folder for searching for images and/or documents from the RadEditor based on the user role. For example, if a user is in the Finance department, they will start in the /images/finance folder.
Additionally, you can secure access to only that folder, and also default the location for incoming uploaded files to be the users folder as well. I hope that this is helpful to someone!
i've posted the information to my blog: