I think it's commendable what you are trying to do, but please understand that in the stock photography industry the term "royalty free", does not mean "license fee free".
"Royalty free" means that the downloading party pays a one-time license fee (at this point on many sites, it's pretty low) to download and use the image for free for the remainder of the license period (which is usually "perpetual"; or "forever").
The benefit here is that the licensing party doesn't have to pay a fee every time they use the stock image.
Of course, there are always restrictions of some sort on how, where and when one can use an image once one has licensed it, but those restrictions are pretty close to what you have above.
Anyway, not trying to rain on anyone's parade, just thought you'd like to know.