What I'm trying to figure out is when everyone's gone to bed (or left the house I guess), and I am hoping I could basically just say if all doors (perimeter, bathroom, etc) and all motion sensors have stayed quiet for more than a few hours maybe, then I can assume the house is either vacant or the guests have all gone to bed. I know I could use 'and stays..' as a trigger, but not sure how to do a cumulative condition like that.
To make it cumulative, just select all the sensors together, and set the trigger to use all of them. There is an option that appears when you select multiple ones.
There are likely existing solutions, most likely part of conversations where people ask why triggers do not include AND.
Separate to that, you make also be interested in searching for the Community developed sensor groups +. Originally developed by @FriedCheese2006 and now maintained by @thebearmay .
This can help you aggregate some of your sensors into single status results.