Gemma,
Have to ask two questions...
1. If you're concerned about increasing recreational flying, would it satisfy you to have a "less-than-PPL" certificate available for less-than-CPL FI instruction received?
2. I'm not questioning your knowledge or abilities, but if you feel you have enough of both to be instructing others, why haven't you done the CPL/IR?
Sorry, on our side there are plenty of "recreational" flyers that move up the ratings scale for personal satisfaction and insurance premium reductions, and never give a thought about actually using their CPL or ATP in an AOC environment.