Since most users probably upload all their files to the same directory, this field could be the default, and if the user wishes to specify a different location for each, they could click a link near the top that will bring them to a different upload page where they can speficy each path separately (just like you do currently).
The same would go for "Who can view this photo?"
For admins who don't like this, they could select which is the default upload form style in the config.