I have always been under the impression that "average difficulty" is the average difficulty of a dramatic action whose outcome is in doubt. It is not the average difficulty of doing that job under normal circumstances.Why assume average difficulty? Isn't most of your work actually easy for you if not down right simple? If simple your math above with an average roll is a roll of 7 skill 0 no bonus, ability average no bonus so 7-2= effect 5, 5*250 = 1250 that month. A roll of 2 might be the equivalent of laid off for that month.
How often do you actually fail at your "normal" work?
You aren't rolling a Pilot check every time you dock your spaceship or file a legal brief. If you have a Pilot 1 or Advocate 1, you can perform your skill competently and reliably. You have a professional certification if such is relevant to that career. The difficulty checks are for *when this specific instance is a dramatic moment in the story*. You check Engineering when you need to not only know if you jumped successfully, but it's important to know if you did before the missiles catch you. Or you need to know just how accurate your arrival is in time and/or space.
Medic 1 could be an EMT or a Nurse or a Doctor. In fact, it is entirely likely that an EMT might be better at first aid and trauma care than a typical doctor. Nurse and Doctors should have additional skills besides trauma care, but that's not generally useful to deal with in an RPG where no one is actually going to be acting as a Doctor as a job. Unless you are trying to do Grey's Anatomy: The RPG. But you could lump that under profession: Nurse or Profession: Physician if it was important in your game.
As a side note, I'm not fond of the argument that normal situations are "Take extra time for +2". IMHO, the task time should be the normal amount of time a person is expected to spend on the task. People should not be expected to routinely "take extra time". Or that "extra" time should be time the task is expected to take.