Fun game, cool way to work in the theme. I liked the beanie bit to introduce the blinding mechanic. The fights and fighter animations felt pretty authentic to me, although I've only ever played the original Punch-Out. The mirror block gave me a bit of trouble at first, because the telegraph animations are long, and I was consistently using it too early. Good job!
Strategy spoilers, I guess. If other people are having trouble after playing the game, here's my Prima strategy guide:
I stumbled into a fairly consistent strategy that makes the game a lot easier, even in expert mode: spam right uppercuts until you're blocked, then spam left jabs, then go back to right uppercuts to repeat the cycle when the jabs are blocked. If you get blocked multiple times in a row, regardless of punch, be ready to dodge. You're probably going to get a telegraphed attack, after which you can go back to spamming. This doesn't fully stunlock the opponents, you're still going to need to dodge and block big attacks, but it does seem to prevent the random quick punches they can throw. I've beaten Expert mode 4 times doing this, with my best "time" being 9 seconds left on the final fight.