Thanks so much for the feedback!
I agree with all that you said wholeheartedly. My team didn't have enough time to playtest our own game, since we were still doing things right up to the deadline, which is why a majority of it feels bare bones. This also lends to the issue of there not being much variety in enemy types, and the bosses not being tested well enough for balance.
We will take what you said and do our best to apply it to our future games!