The lockpicking mechanic is really well done and genuinely fun to play.
I also liked the idea of having different districts. I would have loved to see a bit more variety between them beyond just the difficulty, but the overall structure works really well.
I think simplifying the rest of the gameplay to give more space to the main mechanic was absolutely the right choice. If I had to nitpick, I think even a few simple sprite animations would add a lot, since right now the characters mostly move around as static sprites.
Really nice work overall!