WIY, I do not disapprove of using pictures, but I think that you are abusing the practice – really at your expense more than anyone else’s.
In general, it is best to formulate a judgement of a person without intervening physical factors. When you find a person extraordinarily attractive, your judgement of them will be heavily skewed in their favor – not just in general, but you will actually think they are smarter, calmer, etc. I just read a study about this conducted in the military – personnel that got high ratings for their physical qualities consistently rated higher in every other category. And you can easily see how this applies in terms of relationships by looking at the pattern of celebrity relationships. They very often enter into dedicated relationships and marriages – not just casual flings – only to have them dissolve once they become acquainted with the person on a level beyond the good looks and the glamor.
So ideally, the most accurate assessment of a person’s non-physical qualities can only be obtained by doing research before you meet them (yay shidduch system), without any knowledge of their physical qualities. Notwithstanding, I do understand (not actually understand, but understand that there are things I don’t understand) that as a guy you want to make sure that there is potential for physical attraction in someone that is a potential spouse. So you find a girl that seems compatible on paper, and check the picture to make sure that potential is there. That way, you can get your assessment down and make sure you aren’t entering something that is otherwise doomed to failure.
So by doing what you say you are doing – piling up droves of pictures and finding the most attractive pick from a bunch of really attractive girls, don’t pretend that you’re going to come to any sort of rational decision. And don’t say that all other factors are equal. They aren’t, even if you think they are. And I’m not trying to romanticize the uniqueness of every individual – it is easily demonstrable that no two people are identical in temperament, regardless of how alike they seem. And by doing what you are doing, not only will you not come to any rational decision about whom to date, but you are ensuring that the non-physical qualities of the person you will likely choose will be decided almost completely by chance. Which might work out if you are very lucky…but do you really want to count on that?
So really, just keep in mind that the person you are hurting most by doing this is yourself.