Hola Nick -
xxx
Nice of you to be attracted by ground instruction.
Helping people for aviation theory is as important as practice in flight.
And there are many that need theory assistance, includes even PPL level.
xxx
You are making an effort for your CAA/JAR licencing.
How about making the same effort to get the FAA ground instructor certificates...?
Just a few extra subjects to teach, independently, or with FAA FTOs.
Holding a FAA Ground Instructor ADV/INSTR, you can teach any FAA subject.
A small investment, and certificate never expires.
xxx
Happy contrails