I find that some of the images that I proofed on the computer screen need to be printed smaller while others want/need to be up to 16x20--the image indeed makes the decision.

In regards to small photographs, the Andrew Smith Gallery here seems to get bigger and bigger prints everytime I go in there when they're old Weston and Adams miniature prints were, in my opinion, of the top most interest to me. So precise and intimate. Big prints sometimes feel soulless to me.