I don't think I'd personally try for a realistic simulation of using lockpicks. Instead I'd go for a block sliding puzzle. ... Though, since they are not cars, you could add things like a consumable item that could simplify a lock by exploding one block (or just skip the puzzle), and blocks could be able to slide sideways if they were free along the whole side, etc.
Another way to do it would be (depending on the tech/magic levels in your RPG), using different kinds of locks, other than just the simple key lock. Try combination locks (and have the combos hidden in levels/corpses/etc), computer locks (to pick them, you need a device to hack from and software to hack it), magic locks (could be anywhere from intelligence levels to having learned blueprints/lock schematics prior to picking), and more. There are many kinds of locks, and while it's extra work to program more, it adds variety and challenge to the game.
Great ideas, thank you all; I hadn't considered using these types of puzzles, seems like it would work well, and also by keeping the art direction focused the puzzle components could be made to look more like internal lock mechanics (tumblers, sprockets, etc.) and the puzzle would still look visually as though the player was picking the lock. Thanks again