Haha, it's amazing to hear how many people are really resonating with the guards.
I could absolutely see a version of this adventure though with the guards running rampant throughout the manor, only to solve...very few problems.
I knew that one of the biggest challenges I'd have with an adventure would be getting players and referees interested in running pre-gens instead of their own characters, so I really agonized over each of the guards' personalities, looks, and habits. Anecdotally, I play tested this adventure with a DnD/Pathfinder group that doesn't usually get super into roleplay. It took them less than 20 seconds to turn completely belligerent after reading their characters.