A print exchange is a nice idea but (!) I'm talking about constructive criticism from a larger group. Meaning that a lot of people get to enter a discussion instead of 'just' two people.
I think we simply swapped prints between about ten of us members. One of the forum members received multiples from each participant, made up packs with one of each print, and sent them out. This very generous individual did not request money for shipping (!).
Of note, I think I qualify as a master printer, on inkjet, I'm one of the rare people who do their own profiles and then retouch directly in the printer gamut to optimise colors, so my prints are sometimes very different from what one would get by just giving a file to a lab to run off. I expect some other people here have a similar dedication to the print, so exchanging prints is different from just showing files.
And yes - I do understand such a printing workflow is not portable and suitable for commercial jobs where colors need to match from print to print in a batch, but when you sell single art prints you aren't doing commercial jobs and so you're not bound to the conventional rules of color management. And yes, as an ex-member of the ICC I do know what color management means.
Edmund