You know, it's not as if I was bragging (as if it could be my style), but there are some tours on this website (especially the ones which are around the "dark side of the force"...) which nobody else can perform (yet) because:
1) no one thought of them yet.
2) it takes a lot of work to make them work.
And there are some excellent guides who can only perform very few tours (mostly the blockbusters like Louvre, Versailles, Orsay...) because they didn't have the demand for something else so far but, even though I will more easily find a colleague who can do the Louvre than one who can do the Chartres Cathedral, I'm sure that most of them will be delighted to study some new tours if there is a demand for them. And I have a feeling that those of you who have "been there, done that" are delighted to hear about that...