Still too high imo; players would just keep several more lockpicks on them. The way I see things, one meaningful way to balance this would be to reduce their frequency in vending machines (or have vending machines contain more contents but they would restock only every 3 days; probably bad for MP though), and it should be around 20-25%. This would not render it useless, but it wouldn't also mean that the player could run around with 1-5 lockpicks and crack open every safe they've discovered in the past 30 days.
The issues with safes are:
1. They have the same loot table as similar unlocked containers; why go through the effort of breaking into them early on?
2. Jailbreakers
Hence I suggest that Jailbreakers be much more scarce, they should be nerfed, and gun safes/wall safes/etc. could have a marginally higher chance of giving the player guns early on, or at least parts. Then again though, this could just end up with players getting guns on day 1 again.
Basically, safes are nothing special, and due to the current inconvenience and eventual major convenience of breaking into them, the "safe marking" on the map will continue.