Very cool, I love game music but didn't have starfox growing up haha. Zelda, Mario, Metroid, Final Fantasy games...just didn't get to hear this one.
It is definitely strange in harmony, interesting you heard A minor. I heard G tonality for the most part, it sounded like G split harmony, like the fanfare upper parts were G major (pentatonic?), but there was some clever use of mode mixture, mostly eluding to Gm. For instance, once the bass starts playing:
G |Bb |A |C B Bb A|
...it kinda gives it a split chord type of feel to me (G Bb B D)
I was so interested in that concept I wrote a whole piano piece with that being the "home" chord a while back. Cool stuff, thanks for sharing!