add subdirectory upload destination option for image fields

I created a new type gallery using D7 alpha3.
It allows unlimited image fields (I called them field_photo in the content type declaration of type gallery).
The unlimited option is straight form the setup of field_photo as an Image field.

So I can make a gallery called "album 1" and upload multiple images.
As an aside, I then made a field--field_photo.tpl.php, outputted into a list format
and used slightly modified Galleria js/jquery.

The result is fantastic. I love the way drupal integrated images.

However, all images end up in the same files upload subdirectory and it gets unwieldy
not to mention when you upload dscf0101.jpg from your camera, delete pictures, then for the next
"album 2" gallery type you upload again you get dscf0101_2.jpg.

It would be nice to have the ability within the field_photo setup to:

1. prompt for the subdirectory for this specific gallery's images when creating a gallery content
2. or better, something is just chosen behind the scenes. files/gallery/1 for first gallery type uploads, files/gallery/2 for next one, etc.

I attached a screenshot to better explain.

In defining the image field I can set a subdirectory within the upload directory
for the images but it applies to all galleries so it doesn't help separating multiple
uploads for one gallery type instance.