Sorry, but why do we need to impress them? I agree that manners and common courtesy are essential, just like dealing with anyone else in a service industry and that exceptional service should be rewarded by way of compliments, feedback and possibly gifts but they are there to perform a job for which the passengers are paying for. They are serving the passengers, there should be a book about how to impress passengers, not the other way around, particularly in premium cabins. Passengers don't pay thousands of dollars for premium tickets to then be expected to remember all the crews names and engage in intellectual conversation about the origins of the wine with their meal.
I work in a role where I have clients but I would never present them with a list of 'ways to impress me' - I am paid handsomely to impress them (and this then funds the travel) and I enjoy doing it.