I must have skipped the episode where they removed the lifelines; I agree that was unwise. I suspect at that time they'd never been offshore in heavy weather when you can't walk from the cockpit to the foredeck, but can only crawl, and lifelines are then at shoulder height and very reassuring. I have seen Dan often wearing a safety harness, but couldn't see if there are jack lines running fore and aft.
I have seen numerous episodes where they've used the electric motor, mostly entering or leaving a harbor, occasionally to make it in when the wind dies if they're close to shore. I've had enough experience with unreliable outboard motors and inboard diesels that I like the simplicity and reliability of their electric motor.
Some weekend sailors want to be able to get somewhere on time, or get back to the harbor if the wind picks up, and want the control of a more powerful motor. Kika and Dan are disconnected from clocks, and in heavy weather they reef down or heave to.