Pen and paper is a great tool for RPG and creating adventures for other players. Having a "last will" document on your body in case of being killed or a letter from your wife would give people who find your body a great and immersive moment.

But because most of paper sheets in game are left blank, players do not read them or even chcek if they had been written on because opening the pop up window just to find out it's blank and closing it with the red X is a pain in the ass.

That is because you can't tell from the inventory window if there is something written on it. 99% of players assume it is blank and don't bother checking. Changing the item icon/thumb picture if the paper has something written on it would drastically change usefullness of this feature IMHO.