My dad always used to say after he left work that he didn't know how he ever had time to go to work. He had a full life after he retired.I do not think I'd be bored. I have plenty of hobbies. I am also very intellectual and find new hobbies anytime I come close to getting bored.
Part time isnt an option. I work so many hours now that part time would just mean accepting 1/2 the pay for a full time job.