It's a good idea but it takes some discipline.
For instance if you have multiple people with drug problems one of them will go to town and bring back a supply and now you have people using, overdosing and making trouble.
You might give some people a task like moving rocks from here to there and think it is straightforward but some people need an astonishing amount of supervision to stay on task.
Also dealing with severe mental illness is hard. We had a woman (E) living at our house who I think had schizoaffective disorder who had nowhere else to go; she reminded me of my aunt who suffered from bipolar and some of my desire to help this person came from wanting to "pay forward" the kindness my aunt showed me.
My son was an only and badly needed the sibling experience and being an adult who didn't behave like an adult, E was a pretty good "sister" to my son. Being embedded in our family routine was good for E and she lasted 18 months at our farm which was longer than she stayed anywhere.
One night though she lost it; my son and I barricaded ourselves in the bedroom and called the sheriff but E threatened my wife with a knife and then disappeared into the night.
She came back to the farm to visit a few years later and then passed away two weeks after that.
This place
https://www.wgaforchildren.org/
is well-regarded but it is a running gag that they are always hiring people because it a high stress place to work at.