SAT or SAT Subject Tests?

Hey all, I’m looking to apply to a few colleges soon (Williams, Amherst, Tufts, Vanderbilt, NYU). I’ve taken the SAT twice and my superscore is 1530 (780EBRW, 750M), so I’m not sure now whether to take the SAT for a third time or to take the SAT subject tests instead (likely would take Math II and Literature). I know Williams and Tufts don’t consider SAT subject tests. But for Amherst, Vanderbilt and NYU, the SAT Subject Tests are optional, so they could give me a slight edge over other applicants for those schools if I score well. But at the same time if I improve on my SAT score it would help for all 5 of those colleges, albeit to a minor extent. I’m an international applying for financial aid, and all but one of those colleges are need-aware, so I’m worried that I would need every advantage I can get, and this would be my last opportunity to take either of those tests. Would really appreciate if anyone could offer advice for which test/s I should take, and thank you so much in advance!!!

With both subscores at 750+, I would be done with the SAT and take the subject tests.