Hi Devs.
Here's a little quality of life thought for the game regarding how the game acts when changing equipment via hotkeys.
When you want to equip something that replaces two equipped items - changing from a stone axe & bone saw combo to a shovel for example - and there's not enough space in your belt or you don't even have a belt, then the game doesn't let you.
You always need to keep one slot empty in your belt in order to be able to address for this behavior and be able to switch gears without having to do the switch manually.
I suggest including the player's inventory into this. If there are not enough belt slots free, just put the item into the player's inventory, if there's enough space.
It is possible to equip a hotkeyed item FROM your inventory, but not possible to unequip it TO the inventory.
Belts should always be a priority when looking for available space to unequip items and after that check the inventory.
Maybe add an option in the game settings to enable or disable this behaviour as the player wishes.