Years back I was doing passthrough AR, and spiked a zoom to nanoview (atom beach and towering grain of salt; hardwired to a parking-lot view out my window). Was crude but fun. Intended to go to picoview, to demo a physically-realistic atom-bonding interactive, but it got put aside.
Magic school bus uses "zoom you", rather than "zoom objects". Tradeoffs, but one advantage of "objects", especially for chunked-zooming and AR, is you retain your environment to use as a size reference. Eg, "the red blood cell is M&M sized, and a grain of salt is cardboard-box sized, therefore the table, room, and playground are...".
Fwiw, my fuzzy recollection is someone wrote a simple VR zoomer in unity some years back. Re dioramas, you might find some inspiration from http://www.clarifyscience.info/part/Atoms (very slowwwwly loading page - wasn't intended to be public). I did outreach with a few 1 m diameter tables, each with assorted objects. Pool-noodle floats for hairs, Goodsell's molecular bio illustrations in nanoview, etc. Thought about how one might design a larger exhibit.
But I never did manage to find a community interested in this kind of thing, aside from scattered folks at MIT and Harvard. Size/scale is occasionally taught done down towards primary, and is taught in most every science and engineering curriculum. But knowledge of size/scale is rarely then used to teach other things, so there's little incentive to teach it successfully. With "well, that shouldn't come as a surprise, but oh my, yipes" outcomes.
