I know there are several posts on the inventory management system, but I just want to add my voice to the call. Inventory annoyances; can’t pick up in to existing stacks in the active slots, have to put down things to do inventory shuffling sometimes, hard to determine if attachments are better than the ones you have on your weapon without taking them off the weapon, which again requires more slots- forcing you to drop even more stuff.
I would suggest that if you have an item stack that anything you pick up adds to the stack, even when in one of the active slots. Ability to pick up weapons directly in to a weapon slot, ability to examine weapon details somehow, with all stats and attachments stats. Some sort of color code that matches ammo to weapons, so you can tell at a glance which ammo goes with which weapon.
Great game, thanks!