Maybe choose general traits rather than specific emotion-related traits. By that I mean although Genius is good for that random focused trait when your sim needs that as the correct tone for work it can be annoying when in the next career your sim needs to be inspired. Might be better to use a trait like dance machine (if you have Get Together) as the disco nap fills energy faster then the most expensive bed. Only a little faster but still a great feature. Two naps and your sim is ready to go again, this combined with Never Weary makes for a sim that has no need for a bed.
Reward Traits (click) such as Entrepreneurial do make a difference, not all the time but when it kicks in it can ensure a promotion for that day. Carefree is also good as your sim will never become tense and so can use the work tone 'Work hard' all work shift. I don't actually use this as I like the challenge but it certainly makes a big difference when trying to complete all the careers in one life time, even set on long.
Make use of the longer buffs from packs like Spa Day if you have it. Also the cow plants essences are brilliant for keeping your sims in the correct emotion for work all day long as their buffs last for 12 hours.
Sounds like a fun goal you've set yourself.
