As far as what gets controlled automatically and all that, there’s a saying, “all home automation is local.” Meaning everybody has different needs and different priorities and different devices. 
If someone has a habit of leaving a location device at home, then that particular device is not going to be a reliable presence indicator.
I have friends with a son on the autism spectrum, and they have a GPS tracker device for him (nothing to do with SmartThings) and they ended up putting it into a button pocket on the back beltline of his pants. It was the only place where it was likely to make it through the day.
For people who want to have the indicator but just have different patterns, you have to look at some common denominator. In my occupancy protocol, I have a hat that I almost always wear when I go out. I put a motion detector under that hat, and it going off is what starts my leaving sequence. I can also trigger the same thing by just waving a hand over that motion sensor, or by manually changing the mode in the smartthings app.
If your house has door keys and your wife is unlikely to leave without the keys, then you could attach the smartthings presence fob to that keychain. For other people, leaving a fob in the car’s glove compartment gets most of their situations.
If you’re willing to have a more complicated rules set up, you could set up rules so that if the keychain fob or the car fob leave, then a virtual switch gets flipped as having left and then run everything off of the virtual switch. So instead of “everybody left” it becomes “any of the following leave” but like I said more complicated.
So there are lots of different ways to approach it. The securifi alarm fob is a good solution for many adults because it’s pretty easy, but requires actual physical presence. No drop off problem. And you have total control of the timing. But it doesn’t work for me, because I physically can’t manage that device.
So sometimes it’s just a matter of reading about how different people have approached the issue and then coming up with your own protocol that accounts for your specific preferences and requirements.
Good luck!
for the widgets and tasker integration…interesting that you could use it with the voice integration, does it work with “OK, google”…sorry didn’t look into it fully yet
Say what???