I'll agree with the most recent comments... this was a concern in the past, and the solution was to add "comments welcome" to the description text. I keep forgetting to do that, so maybe a check-box for it could be added to the upload form.
I think uploaded pics should default to the "comments welcome" condition, as it sure would be awkward to specify "comments unwelcome"! Fair Game, and all that, it seems when you upload your picture, it's naturally open to comments good and bad.
We're very fortunate to have such a helpful and polite membership, who don't drop acid criticisms on others' pics.
I often think that I'm not qualified to judge the uploads, but I guess that comes from a reluctance to work at generating a critique of just any random image. I do comment when something useful occurs to me to say. Unless specifically asked, I tend not to comment on those that strike me as "blah."
That's not to say the reverse is also true: Just because I don't comment doesn't mean I wasn't impressed! I simply wasn't able to think of anything useful or helpful to contribute. Well, I guess it WOULD be nice to say "great image" or something like that, if warranted.
I think it's definitely NOT useful to comment like, "crappy picture, just a boring snapshot, you don't deserve a Leica." That's simply denigration, not a critique, and all too common in Photo.net. It can be said in a much more positive and helpful way, with just a little thought. 😉
I would oppose a separate Critiques section of the gallery, or a Favorites section either. Fair to assume I think that ALL uploads are favorites that are available for comment. Why would you upload a pic you don't favor, and then refuse comments? Well, some shots are illustrative of technical points, and this should be made clear in the description.
Ah, descriptions! SOME sort of descriptive commentary is nearly always helpful. I like to know approximately where in the world the shot was made too! Please fill in the other blanks in the form as well, as this then allows for good gallery searches. For instance if I wanted to see some pics developed with Diafine, the gallery can be a good research tool.
I think it's a good idea to look over your gallery uploads from time to time to weed out any that you might have favored at the time but which now seem less worthy. But not just on the basis of comments received; uncommented ones may still look good to you.