Recall too that the term "traps" in adventure design can often be interchanged with "obstacle" if it suits the situation better. If you don't want your players to fear every square of hallway, make hallway traps into obstacles instead - obvious problems with non-obvious solutions.
Your pit "trap" for example - yes it makes no design sense to have a pit in a thoroughfare, especially if things are moving around in the area. Instead of an intentionally designed pit trap, have your pit be a section of collapsed floor that's just a weee bit too wide to simply jump over, and with some serious discomfort hinted at if the party tries to just climb down > walk across >climb back up (like a zillion rats roiling around, or water of indeterminable depth, or whatever at the bottom).
This way you still get the same fun that you would with using a trap (and less malicious player vs. DM "gotcha" gameplay), and it seems more natural to be in there. And you don't need to worry about ham-fisted warnings and telegraphing things to the players beforehand.