No idea if this has been suggested befor as im too lazy to scour the forums,but what if a player had the option when they travel abroad to risk smuggling a few extra items back.
The success rate of the smuggle option could be tied to a players natural nerve and crime skill,like other crimes.
Higher natural nerve could increase the amount of items you could risk smuggling back on top of your personal carry total,higher ce equals higher success rate ect.
A failure could be a player is detained for questioning and rectal examination abroad for X amount of hours (Maybe detained for the time of the journey taken,or a big % of it) befor being sent back to the country by customs ect,maybe even have the items they bought on that trip removed and taken off them like customs do.
Idk use your imagination.