With exception of the minigames, those things you mentioned were intentional. I'm not a fan of tutorials, so I was expecting (hoping, really) that the player would be able to figure things out by poking around. As for the soundscape, the feeling I was going for was: working alone in an empty workshop, so if it gave you the impression of an empty space, then I succeeded.
Without the time to have people play-test it, it was all a bit of a gamble.
Thank you for your feedback.