It's really personal preference. I am average height (5'10"), so normal kitchen counter height works for me.
However, when I installed a sink for trays, I built the stand so that the bottom of the sink was at counter top height, i.e., the trays were at the same height as they would have been on a counter. One wouldn't think that 6 inches (or so) difference would be significant. But bending over that far to reach all the trays will add up.
So, bottom line: build, buy, install what's comfortable to you!
Cheers
David