Maybe add a chop shop to sell stolen cars. This will add more things to use lockpicks for. Here are some basics to make it fair.
Up the price on lockpicks to $500 - $1,000 each
Cooldown 1 every (1-2 hours)
Selling Price
Economy $1,000 - $4,000
Luxury: $5,000 - $8,000
Super: $10,000 - $15,000
Make it so people can buy their cars back for $1,000 more then what it was sold for.
Make it so people can't sell their own cars.
Make it that people can't spawn back the car that was stolen from them.