Well, then:
1) Why is the upgrade hitbox small? This is a technical issue. The hitboxes literally overlap each other, which is why I had to go for this temporary compromise.
2) Why does the wrench keep being removed? Initially, it was meant to make the game more challenging. Later, I realized that it was a bad idea...
3) Why the right mouse button? Because it was more convenient to test the equipment removal mechanic this way.
In the end, I would say that this prototype turned out not very good. (I understand that perfectly) But the project will continue to live and develop.