Hey, thanks the feedback.
That would be one of the ways that I'd use the home functionality, but the categorisation would allow for more niche subjects than just generic local conversation, such as treasure hunting games or historical photos etc. Also, the nearby feature would make it more of a utility for travelling and sightseeing.
I think you're right in that uptake would be a challenge, but I personally think that would primarily be due to the paradox of not joining a community because it's empty. It's something that I mention in the article. I don't know if it's something that can be overcome, but I wouldn't mind giving it a go.
Hey, it's good to know that others have been considering this sort of thing.
My article does detail solutions to some of the issues you've raised here, but I'll go over them each just to see where our visions differ:
All posts will have a publicly available URL. I don't think it would be good to create closed communities, only solutions that would show the user local posts.
I don't believe we should validate that people actually live in the community. I think administration of blocking malicious users should work just like Lemmy, but I don't think the potential for abuse is quite as high, given that the reward for a spammer would be to spam to such a small amount of people. There's less work in spamming to a larger group by choosing just about any other type of community.
You don't, just like Lemmy and Mastodon, your account on one instance could be used to interact with other instances. The Connecting Instances section of the article details how this could work from a technical point.
Distributed cost and administration is exactly how I see it. I would only care to host my local instance.