Congratulations. What an amazing game. Everything was great - Music, art, and the game itself. The story was well written and the endings, especially the "special" one, are all touching.
If I had one suggestion, it would be simply fix the few typos that sneaked through text revision. I can't pinpoint them as they are kinda spaced out - I didn't skip a single piece of dialog.
And if I had another suggestion, it would be to distinguish better the invulnerability time after doing an overdrive. I believe it is hard to spot when a purple glow stops turning blue - I wasted much of overdrive invuln. time afraid of taking damage. Players with color blindness may be even more troubled to dintinguish the difference. A "purple bubble", distinct from the ship blue shield, would be a fit.
Then, this game would be a complete masterpiece.