for this one, I think you need a bit different framing or you need the people in the background to be doing something interesting to add to the photo (and shift it up a bit so the guys head isn't cut off). Other then that the exposure looks good.
nice framing on this one, maybe a tad underexposed but I'm not sure what you were going for or what equipment you have to work with so I can't be to harsh. I do like the use of decisive moment on this photo though and you captured the motion very well.