Thank you for playing and for the feedback. I will consider some.
I'm working on rebalancing the loot drop so the chance rates aren't too extreme low or high.
The sound hasn't been implemented yet. Sorry. I will add it next to the save system in the upcoming update.
The mechanic behind the inventory screen was only meant to take a look at your belongings. That's why the holding down the right mouse button. But I will also change that by disabling the buttons behing the screen as you mentioned.