6 hours? No. It'll be a week before a player gets his/her job.
The requirements and different prices both sound good to me. I think there should be a certain number of play hours for certain jobs, ex: tour guide since it has to know the city well.
I think 6 hours is too much of a wait and will make people, especially new ones, leave the server instantly after failing an exam.
As for the price (or potential change of waiting time), I'm sure the DoE will propose some changes if they believe it to be necessary.
I'll tag Minister @enderhusky414 just so she could be notified of this suggestion and work it out with the Department if found necessary.