[ben_w]

This reminds me, I think the normal measures of population density aren't very helpful, but I'm not sure what to replace it with.

If Alaska seceded, almost nobody in the other states would feel the difference, but the population density would jump 15%: https://www.wolframalpha.com/input?i=%28%28population+USA+-+...

(Or in reverse if Trump acquires Greenland — with no real change to people's experiences, the population density would go down 23%: https://www.wolframalpha.com/input?i=%28%28population+USA+%2...)

Likewise Australia, the outback is about 70%-85%-ish of the country depending who I ask, with about 607k people in it, so if the Aboriginal Australians were to secede with it, the rest suddenly gets x3-x6 the population density with no actual change to their experiences.

[Kubuxu]

I think what would be useful is a histogram of population densities, or for example a percentile based metric: population density covering 99/95% of population.

[ben_w]

I'm thinking something like "From the average person's perspective, how many people are within 100m, 500m, 1km, 5km, 10km, and 50km?"

The questions that seem to matter, and for which population density is a proxy, are: how crowded does it feel, and how easy is it to get to the socioeconomic advantages of being near other people (infrastructure, commuting, shopping, community sports, faith buildings, pubs, etc.)?