He had a quiet calm. But he was strong when he needed to be. Fred MacMurray from 'My Three Sons' is another role model. Mitty's flights of fancy could explain the mind trips Hal takes from time to time. Although no one has specifically said what Hal does, Cranston assumes he's a systems analyst.
Most people work for a living at an occupation that was available.
If the person next door is a house painter and he needs someone to help him, you take the job. Flash forward 20 years and you're a house painter. Most people don't get to go into something they're interested in. If I was going to succeed as an actor, I had to give up any thought of trying to control things outside my realm. Now that he's solidly entrenched in television viewers' psyche, the malleable actor knows this could be his one shot.