Dude, you could've easily made money out it. I for one would've definitely bought it. Your product is superb, simple and gives us capability to add stuff on top of it like authentication
Providing this tool for free is a cost to you.
Sure, allow a certain number of photos free of charge and charge for more.
Great software anyways! Thanks!
Why be more imaginative? It sounds a pretty simple offering to me, and is highly transparent.
A hosted variant isn't a bad idea (I was going to ask if there were recipes for EC2, Docker etc... some people might want to "self" host on a machine they control) but it's more "value added" than the original codebase.
if you buy something, people expect someone to be responsible for the product. This mean you got to spend time on providing service, or it get defined by most people as a cash grab.