Revised the plan about picking up items
After reading some trying the current system for a while and reading some feedback, I’ve decided to keep item pickups as walk-over.
The main reason is that throwing items works pretty well now without having accidental pickups, and having thousands of items laying around will seriously hurt the framerate. So instead, items left on the game can be picked up by anyone getting close to them, to encourage picking stuff up, and they will vanish after a short while.
There will also be chests that you can open (by pressing e, perhaps) to store large amounts of items without them vanishing, or risking picking them up.
Another game balance thing for the future will probably also be to allow several stacks of the same resource, but limit the stacks to, say, 32 items or something in the inventory, but leave it at 99 for chests and other containers.