Whatever the standard is for a bathroom vanity.

For better comfort, I'd go with 26-28" depending on how tall you are.

There is no standard for bath vanities. Cabinet manufacturers have what they call vanity bases that allow for a 32" countertop but most clients these days seem to prefer a 36" countertop height for their vanities. The exception might be for bathrooms primarily utilized by children. I would set the top of the bowl rim between 32" and 36" but do some experimenting and see what seems the most comfortable to you.

My point was that you keep in mind the comfort of where the COUNTERTOP level lines up with your body...not so much the level of the vessel sink.

I agree motherbear, the height of both elements should taken into consideration.

So, how high is the mirror going to be with these wall mounted faucets? Too high?