I'm going to offer today's fit as an example of when gray trousers would not have added anything to this. I believe that the trousers I selected are not only just as good as gray, but actively better. Gray would have offered contrast, but no tonal similarity to tie the colors together. Take it or leave it, but that's just my suggestion. Apologies if no one cares about this discussion anymore.
Closeups and shoes (Click to show)