Thanks so much for trying it out and giving this detailed response! Yeah, I definitely think that the base of this game could easily be expanded on to support more aspects of chemistry like double and triple bounds, and I'm sure there would be a solution to managing more complex molecules. I really like your idea on incorporating the electrons more physically within the game and I think that could result in some really interesting gameplay with trying to catch electrons flying around the place.
And yeah, for the visuals on this game, I think the artists on our team did a great job at giving them individual personalities in their design and move set. We tried to make it at least somewhat reflective of their action properties, which is why carbon is a huge tank enemy and oxygen shoots out blasts of "wind".
And finally, I am fully in favor if you'd be interested in sharing this as a quick introduction at a stem camp, especially once we fix some of the issues/bugs, after the judging period is over, that we didn't quite get to in time.
Thanks!