Re: Amuse me, sailing small boat offshore.
Self steering is a topic that you could research. The point is not that most people in small boats die, but that most who daydream about it stop there.
On a practical basis the costs of the safety gear required including life raft mount up and can exceed the cost of the boat. Sure you may not need a liferaft, until you may.
Again on a practical you don't down sails to sleep, one because the motion would be uncomfortable, and two because the loss of distance in what would be a slow boat anyway means that you have to carry much more water etc which is heavy and takes up space.
I don't recall the details of sheet to tiller steering, but doubt that it would be very effective for constant use. An autopilot is heavy on power and would require probably two batteries and a quite large solar panel. More weight and space. They are also noisy and prone to breakage so many take two. The best is a windvane but they are not cheap and need to be tailored to the boat.
While most have sympathy for day dreaming and will help with specifics, some might be a bit sceptical about a "tell me all I need to know" approach versus reading the books available and searching out the threads on specific topics.