So I've been playing around with a lot of different builds and my Wood Elf Warlock is a fantastic pickpocket.
He only has 14 Charisma until level 4 (where he'll get a bump to 16), but with the Friends spell he has advantage on Deception, Intimidation, and Persuasion checks you need to make after someone realizes items are being stolen in order to maintain your innocence.
He gets the following skills:
Charlatan Origin: Deception and Sleight of Hand.
Wood Elf Race: Perception and Stealth.
Warlock Skill Choices: Intimidation and Investigation (The best INT Skill to take).
Beguiling Influence (Level 2 Warlock Choice): Persuasion (Would also get Deception Here, but there isn't a better origin than Charlatan currently for this build).
So he can pick locks, and find and disarm traps using Thieves Tools and Trap Disarm Tool Kits (though I'm not sure if this is a bug, and if he shouldn't be able to use these without proficiency in Thieves Tools).
And he can pick pockets.
NOTE: Shadowheart also helps here since she can cast Guidance before you hide and pick pockets in order to increase success rates for stealing. And again, you should also cast FRIENDS on your mark first so when they talk to you afterward you get advantage on any CHA based rolls to maintain your innocence. Always steal all their money first so if you have to bribe them on failed rolls it's pennies out of pocket from there.
Basically this is a "Super Thief", and more proof that Rogues need Expertise like with the 5e rules to improve their rolls a bit. Otherwise they can't keep up with the Warlock. I can fleece a hole town this way.
"Old time love song will die so swiftly.
You never trust me-
For a while it was nice, but it's time to say bye....
I'm cold, you're so cold-
You're so cold, you're so cold-
No-no-no, cold, you're so cold...."