Running into the same issue with multi-image field and the limitation that has been commented on for two years since it was introduced. The fact it can only be used on a template page is a major problem. One fo the biggest use cases is for exactly what you are talking about.
lightboxes, sliders, to create a page that shows multiple galleries not having to click to a template page and then access it.
It’s not a great solution but I guess it’s to continue using a collection for images and sort them with references or options. Also a limit of nesting 5 items in a collection makes that useless as well. Glad finsweet has a workaround for that. Because without that workaround you can’t even have more than 5 images.
For instance - A static page with a dynamic list of photographers, with a dynamic list of photos nested in it. Possible but limited to 5 nested items. I get there has to be limits possibly for load times etc but 5? This is a major hangup for any type of gallery site. But since it’s been two years I guess the workarounds are the only option.