The unfortunate answer is that I've got so much on my plate, within nostr and in the rest of my life, that I don't have the time to even help design such a thing. But it sounds interesting. There are reporting events (kind 1984) were people tattle on others you might want to use. And there are reactions you might want to use as scoring too. I think it will be unreliable and easily gamed unless it is very well designed, and also many people will not want to participate in disclosing their location (People know I'm in NZ now, but previously all I ever said was that I lived in a volcano lair 2/3rds the way around the world from wherever you are). So there are a lot of challenges.