redeyedfly
REGISTERED
I would certainly discuss using an optional, more restrictive, code with your clients before designing to them.Granted but where the 2017 is more restrictive than the 2009, it might be better design to use the 2017. I can't speak for every situation and condition, but the minimum sizes for wheelchair spaces and maneuvering space have generally increased in 2017, usually for good reasons. But then I'm a designer and consider code minimums a necessary condition but rarely sufficient for good design.
While your attitude may be admirable to some, the choice to go above code is not yours, it is the choice of whoever is paying for it.