I've just read the ghost hunter guide after having taken a pre-existing sim to level 10 of that profession, and I have a couple of observations. First, he didn't have the Brave trait and was never afraid of the ghosts he was hunting (although he did get his feelings hurt by one of them who made fun of him!). Perhaps that trait would speed up his rate of advancement, but he did just fine without it, reaching level 10 in just over 2 weeks. Second, some of the posts on the forum have suggested it is best to start with a low level of required skills so your sim can gain experience as they gain skills. This sim had level 10 logic before starting his ghost hunting adventures, and I don't think that delayed him. I did notice that what was supposed to be a 10-hour shift, from 5 pm to 3 am, was usually more like 4 or 5 hours for him. I wondered if that was because his high logic skill allowed him to work faster. Does anyone have any thoughts on that?