Congratulations!
What’s your play style? How heavy are you on knockouts, noisemaking, optional loot, etc.
At first I was very heavy on the knockouts and looting, but after some time of playing I found that a more passive style works a lot better, since having guards on high alert makes things very difficult. That usually left me running out of time before escaping, but it also meant that there wasn't any punishment for grabbing the bonus loot after getting the required loot.