[really, really Infinities] strange things are afoot

[M Fnord]

Still, I wonder if the Fen could stay relevant in the Solar System unless Earth decides "the area is not worth the effort".

It really depends on how you define relevance. Will the Fen ever be like they are in the mainline, commanding the heights of the solar system? Probably not. There's not quite enough of them (though more on average than in the mainline) to offset the advantage Earth's population and economy offer, even with miracle technology.

But that doesn't mean they're not relevant. The Convention operates out on the ragged edge of the frontier, which gives them a certain frontier mystique. People join the Fen on a pretty regular basis - especially people who'd like something better in their lives but don't want to live under the Space Powers' collective thumb. Also, the Fen aren't simply lurking in holes in the outer system, they're actively involved in shaping things. They may not be the political force that they are in the mainline but they're much more of a cultural force, which may turn out for the better.
Mr. Fnord interdimensional man of mystery

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