hey Craig, okay, I'm writing this down as an idea, but not sure if and when I would work on this.
If you want to, I can code this for you based on your specifications so you would have this quicker, but it costs €90 per hour.
hmm thats not possible :/
i think in your case you could use the fullscreen slider plugin
and use the horizontal option
this will turn your gridder rows into slides
then use row background images for the fullsize images and use normal image elements for the other images
also set "Max-width and max-height of elements" to 100% in lay options → fullscreen slider images
you can try to set it up like this for just one project to see if that would work