The separation and comparison sound like a good idea! Seems fitting to combine with safety and risks.
In terms of history I thought about beginning from the start, continuing with the mining+inflation and therefore the birth of new, more stable currencies. (don't know if I should include this for fun as well: https://www.youtube.com/watch?v=oatx83Gy8kE note it's for a good cause as well hehe (1min22sec))
Then following with micropayments and future tendencies/potentials. So the past, the present and the future are covered.