I think it would be really interesting to add another function to writing tablets: /seal and /unseal.
When you have a parchment or piece of paper in the writing tablet, you can type /write or /title to add text to it. But what if you want to keep that text a secret? How about adding /seal, which makes the parchment unidentified with a lore requirement of about 100 or so. Then, anyone who has that item in their possession can put it in a writing tablet and type /unseal, or else carry a letter opener (a no damage dagger with reduced weight, that lets you use /unseal without a tablet.)
How about it?