The idea
First of all I would like to just say great job on the program so far, it's easy to use in all the ways that matter and on top of all it actually works.
However I would like to request the option for an alternative local file structure. Right now it's all saved as a mixed bag in recursive folders based on the file ID, this is fine and all if you just want a copy and only of one user but when you want to browse them with an image viewer or have multiple users it becomes a bit of a hassle, if at all possible i would like to request the option to at least have it separated by user(i'm personally a bit partial to the format: "(author)/(upload_date) - (title).(ext)") although ideally if it's not too much to ask i would prefer a user defined structure using the values it is already saving to the database anyway.
With that said keep up the good work I really like the program as it currently is already.
Implementation ideas
have a section in the database where the user can either specify one of a set of predefined folder structures or the option to enter a user defined structure