I've come across this issue while building a clients webpage. I want to let the editor to upload several images at once and design it as a gallery section in my layout.
The only solution suggested here was creating a new collection and add it as a reference. But the problem here is, if I have 10 or more images to upload this becomes a really annoying activity, both for me as it is for the client when the times to upload this amount of images comes.
It would be really usefull to have field called "Image Gallery" as a Content Field inside the Collections editor.