Thanks for playing and for the feedback! We really appreciate that you took the time to help us out :) To address a few of your points:
We will be working on mouse and keyboard support as we approach release so we can have feel as nice as possible.
Music is currently being composed for the entire game, unfortunately we didn't have it in time for the Beta
The menu art is not final and will be working on that in the coming weeks also
We will definitely be tweaking the audio in the cave, especially if its annoying!
Thanks again for playtesting, this feedback will help us alot :)