They can easily be made with springs and magnets. The reason they are not included in the basic kit is because they would technically be 'small parts' and I wanted to make Snatoms safe and accessible for all who want to use them.
I'd like to! I wanted to start with the simplest kit that would be useful. In my opinion that's a kit for glucose since cell respiration and photosynthesis are such important processes. We may add more elements as stretch goals, or make more advanced kits.