Standards higher? Possibly, but then it may be that most microlight instructors are doing it as a professional job in itself and not as a stepping stone to "bigger" things.
So they have a wealth of experience, and experience is a great teacher!
Other than the simple conditions set out above, you will also need to have a microlight FI to work under as an AFI and one who will mentor you, select suitable students for you and not just have you doing trial lessons all day.
Unfortunately, you may also find that many FIs will pay you almost nothing as an AFI because of all that.
Find an FI willing to work with you first - one way of getting the most out of your 40 hours in micros - and then think about the instructor course.
And be aware that many schools don't have unlimited resources and it is hard to lease microlights, so you may end up having to buy one of your own to teach on.