Sorry for the incredible late response. I'm just now, if you can believe it, learning how to follow threads, and I'm playing catch up, where appropriate.
I've never used Google photo, but I'll check it out. I do my photo editing in Photoshop, but I'm guessing the sort of grid you showed above would be easier to create in Google Photo.
I love the idea of showing color variations and even bloom conformation that way. I see it often in peonies. A single photo of a flower or leaf of a plant really doesn't begin to tell the whole story. Now I'm inspired all over again to create some useful composites.