But we weren't talking about picking it up. My comment was to use your original idea, but make it automatic.
And regarding picking it up, that's the one and only instance where picking up something that is filled with stuff ends up being a bad decision. Since you can only have one drone at a time, you can't fill more than one up with stuff. And if you pick it up even when it's full of stuff, you are actually losing one inventory space compared to leaving it flying around. It isn't like a vehicle, where you can have as many as you want and could fill them up and then carry a dozen around for extra space. With only one, it doesn't actually help to pick it up when the inventory is full. So I think it would be fine if they let you pick that up when it has a full inventory. But there also isn't much reason to do that except if you want to keep it "alive" during horde night or some other larger fight and it happens to have stuff in its inventory.