Thanks for the feedback. I will use your comments when I design future levels.

I liked how throughout your level you made it so that every room feels like an actual location.
My main comment, in case you want to make another map, is to be more conservative on the amount of coins and NPCs. Even though you may it may make sense for there to be more people, it detracts from the gameplay. A few minor comments are that it is a good idea to give your players multiple stairs to change floors and to keep track that your stairs line up. (You have one set of stairs on the roof that goes down connected to another that goes down below it.) It is also nice for players to be able to see the direction they have to enter vents. You can do this by removing the wall tile where you want to put the vent entrance.
I know I mainly commented on negative parts, but I want to make it clear that I enjoyed the level. Hopefully you decide to make more in the future.