I think the results would be more telling if instead of tracking the amount of days to promote, you tracked the performance meter instead. This is because performance gains cap out and don't carry over to the next level.
Just to give an example of what I'm talking about, let's enumerate the amount of performance it takes to go from level 9 to 10 and say it's 1500.
If a normal sim gets 500 per day, and a sim with all the bonuses gets 700 per day, it will still take both sims 3 workdays to promote and the extra 600 that the second sim earned goes nowhere. So this might not necessarily mean the traits aren't doing anything. This may (or may not) be easier to see on sims that don't do the daily task, don't work hard, and don't go to work in the right mood. But yeah, it is totally possible that they just don't work properly.
