I agree with BEagle on this. I think the FI rating should be a stand alone device that allows the holder to be paid no matter what licence they have. It needs to be more difficult and longer course overall to ensure standards are kept up or even improved.
Whilst occasionally having ATPL theory knowledge may seem useful, it really isn't if you are teaching purely to PPL standard.
(Though I don't differentiate what I teach compared to whom I'm teaching. They all get told the same old nonsense!..)