The second one is probably the best out off the bunch, but i'd say you've probably got too much foreground in it, so I'd either crop the bottom out, placing the person in the bottom third of the photo. You could probably do some adjustments to the levels to bring out more detail in the sky too.
Forth one is nice, I'd probably add a little motion blur to it,as I'm sure the grass would have been moving in the wind. So maybe try that on a slightly longer shutter speed.
The cloud one is the same as the rocks, you've got the foreground beach doesn't do anything and the diagonal line takes the eye away.
The piano I'd probably do in black and white.
The bench and VW are nice examples of DoF
The rock in the wash, does nothing for me, nice example of a higher shutter speed.
But the second one is good, and with some slight PP can be a cracking shot.