This isn’t a legal proposal, as it wasn’t submitted in the “Proposal” category.

  even though it isn’t a proposal. The price should be higher.

1200 points, perhaps.

Also, it should be “any player may achieve victory”, not “any player may declare victory”. Anyone already can declare victory per the Core Rules.

DoVs are fairly informal, we don’t need to worry about being too precise about wording this kind of victory condition. Nobody (well, nobody much) would vote against a DoV because the agreed victory mechanism used “declare” instead of “achieve”.