Reverse pickpocketing would be interesting to add. I doubt it'd be able to complex enough to do things like implicate someone else with stolen goods BUT, in the vein of fallout it could serve a function that trading doesn't, forcibly affecting someone with something negative.
Being able to affect someone with a poison or put something harmful like a flame arrow in a NPC's inventory so they get poisoned or combust into flames could be quite fun to do, runs the risk to being discovered but with skill the individual character could avoid being discovered at least the first time it happens to a NPC group.
Also most characters in the game are not spellcasters and in fact by base 5e design most are not supposed to be able to use scrolls.
