Using ELK stack for end user?

This may be a bit odd of a question, but our team is exploring solutions to a project. Our project involves collecting online image data and allowing an end user to view and search through the image dataset. Initially our team went with a MySQL / web app stack solution to do this. A team member of ours suggested elasticsearch as our main data store and the ELK stack as a solution for the end user. I am wondering if this is feasible or even intended for an end user. It appears though the elk stack is more for admin users to provide analytics on their own data internally behind the scenes. Not for an actual end user to use. I also see that elastic search can be used as a full text search to work in conjunction with some other full stack solution as well.

With that said, I would like to know what applications should the ELK stack not be used for and where does it shine?

If you have an interface between your user and the data, does it matter what it's stored in?

That last one is a bit open ended, there are many, many use cases for ES.
I probably wouldn't use it for binary data though.