Hello, as many of things that concern me in this game, inventory system is one of the most unbalanced and exploitable thing.
It bugs me out in almost every game.

Basically in barotrauma you can have 10 items, regardless of their weight or size, even if it is morphine syringes that 10 in real world can fit in hand.
It is exploitable by crafting toolboxes, that you can have 10, and then 120 items in inventory, pretty much making you a wagon.

So maybe consider that 10 inventory slots should be an hmm just access slots to inventory, and inventory itself should be somewhere else.
Toolboxes should be placed in hand, so one can move max 2 at time.
Naked characters should have two inventory slots - their hands, and if you consider traitors for real, consider that you can hide items in hair, mouth and other orifices.
Items should have weight (density), so going out for mining without at least electric scooter, will make one lost buoyancy and go to the bottom like with concrete shoes.

I don't know what idea is better for devs, box idea, stack idea, grid inventory, grid/pocket inventory combo, but current system is bad for small items, and exploitable for big and heavy items.
Personally, i would love system, that incorporate pockets in clothes, more clothes you have, more pockets you have, especially for military clothes that basic trousers have six cavernous pockets. Even hidden pockets for traitors, for example in one of my old trousers i had small bag like pocket sewn from inside near belt area, so when you wear a belt, it almost impossible to detect in basic search by hand, even helmets should have some small space for items (photos inside helmets, tape like pocket outside helmet for cigarettes)
Then we have "water" inventory - if you will go outside with diving suit, for mining or other activities, i will take a spacious net like bag, that have almost infinite volume, but slows you down the bigger it gets, and have density/weight that could make you have buoyancy problems.
And last thing - boxes - lets go back to morphine as an example because it will be similar to every small items - wires, bullets, batteries ETC.
You can have a small 10mg military syringe of morphine, then you can have box of 5 of them, then you can have bulk box of small boxes like 25 of them that can barely fit in big pocket. But there is other thing, no normal doctor will use it if they have a 250ml bottle of morphine with them and reusable glass syringe (consider contamination from previous patients) that can administer exactly the dose that is needed (and the skill could determine that the dose is perfect or not)

Thanks for reading, if you read it all,
my English is not perfect as i want it to be, so sorry for it but i hope that the idea is understandable.