[ncmncm]

By then we will have pB fusion, and have no need of solar arrays. The Kuiper belt will then be more attractive than the asteroids. There is plenty of frozen nitrogen there, and abundant precious cold.

Heat is easy to get, fundamentally hard to shed.

[PaulHoule]

D + D probably wins in conditions out there. The T and He3 that it breeds will be handy.

My guess is that anybody who gets out that far loses interest in dry inner solar system planets completely and isn't going to be interested in exporting products back.

[ncmncm]

By then they might be most interested in getting as far as possible from any nearby magnetars and other existential threats.

Although other people might be the most immediate threat right up until the moment a magnetar sterilizes the vicinity.

I don't know whether we are certain where the nearest one is.