I think people could be paid according to how productive and beneficial their works are to society regardless of how long they work. The benefits should be good or add to the quality of customers wellbeing, or to the satisfaction it brings to their lives. This could push workers to focus more on things they are gifted in and spend more time with them, not necessarily at their offices/companies, but places like homes.
Your work needs to becomes part of you, assuming it's your role in life, as that is main reason you exist in the first place.  If it's something you are gifted or talented in, you would be enjoying it alot with the accompanying health benefits, and you wouldn't want to spend less time on it.
Rewards or money ought to be secondary othwise it becomes the main reason for working and less about passion. Passion could make people work harder, better and longer.