Deswitch: not really, also depends greatly on site situations, quite a norm to say that I use F8 or above (smaller aperture) to get the DOF, but then, at that distance, the depth is only so much, so we tend to try to get the subject as parallel to the body as possible. But there are situation we can't do that, maybe due to obstruction or a muddy ground ;P
Bluesteel: you referring to #3 and 4 ;P, the position of #3 is done intentional, to add to the composition. for #4, no choice, unless I snap that flower away ;P..keke