This is just my personal preference, but I prefer females. I also like the laid back ones the most, they seem to be able to focus more in the field, and it also makes life easier at the house. As for color, I would look for the dog that meets the first two criteria, and take the color that matches the first two.
There is no such thing as a cripple being too close!!! If so, you might never see it again. I'm not going to take that chance!!!