This looks great! My half-baked notation (if you can call it) I intuit into is similar but, as I said, half-baked so I found it tiresome at some point. Also I needed that bit of advice on keeping the flow.
I have started to write down combat and notable events at each session I have with friends, because it's hard to remember all epic moments, when we have problem with scheduling... I hope this notation will help.
I would change --- blocks to === or some other since at least in pandoc markdown --- is meant for YAML blocks.