Updated Burglars who can actually rummage through your dressers/drawers/cupboards, if they're ambitions or have a high mischief/handiness skill they could bypass alarms/locked doors meaning your last resort would be a brave sim okay with sleeping nearby or camping at the main door (Maybe paranoid sims or sims who've been ransacked more than once and have an obvious bad relationship with the thief), or even getting a dog or two (Or cat, which in their own way could alert everyone or scratch up the intruder).
refresh the klepto trait so you can become a burglar or just steal bits and pieces you like from locals!
Give escaped burglars the ability to mock you with letters/photos of their loot sent via the mail, or even return items if the family have young children or are low money wise.
If your household has one or more moody teens they themselves can act as an alarm, either screaming the place down and scaring the sim off, waking up the parents or being just so angry they pull a broom out of their pocket and chase the burglar outside.
Like other sims series you can arrest them if your sim is a cop, or influence the courts to make their lives hell inside prison should you take the lawyer route.
Active burglar career (Obviously), forcing you to make your own decisions as to whether or not to steal from your friends and neighbors.
The chance for elderly sims to die of fright from an intruder (Leading them to run or put their hands up like "I didn't do that" or hit them with a cane)
Child sims being able to set traps Home Alone style! (With less pain)
Finally...Toddler sims leaving lego bricks on the floor for the thieves to step on, scream and wake the whole house.
