>>96509976
I mostly use ACKS which has an Abstract Dungeon system with my own shitbrew on top. The default risk taking was 6 encounters of a floor that matches their party level which would translate to the 18 rooms. Each party then had their own penalty to the roll that they would find acceptable so you could have more or less encounters. So the one time the NPC party full cleared the 1st Floor was because they got rolled up as the first party of the week after a reset, they were the highest level group, and the path to the later floors wasn't cleared out yet so got assigned the 1st floor. This was a simplification in my system since I didn't want to have average shit out across multiple floors so I just set it to whatever floor they had access to they would do. Being higher level they could take on more encounters before they hit the penalty they found acceptable which ended up being enough to clear the whole 1st floor.

Had a Discord bot that would post each weeks forays at the end. I mostly did this to try foster competition in my parties so they would do more shit and stop being so cautious. No one wants to get upstaged by an NPC party so if they see that some randos pulled in 20,000 GP they'll want to pull in that much as well.