Great pics. I also try to shoot as many different things as possible. Variation is important i think. Off course i dont go around as an headless chicken but think before if it makes sense. But in general most things can be useful. Some more others less but there are many buyers. I also shoot less popular things. There could be somebody looking for it and nobody has it because most of us try to shoot only popular images. But i always think before if it could be used in some article.