I'm with Klas less the understanding (I try...it's a huge part of success on here too so don't quit for my humble sake!!) :0 I absolutely LOVE the composition with the boots. Have about ten pair around here of those hard working soles of a hard working soul. ;)
I like this one a lot, but you have some sharp edges in your composites that I feel detract from it slightly. One way to soften them is to use a big soft black brush and soften the edges on the layer that's showing edges. Also sometings using screen or multiply blend options will fix it (or make it worse). Your work inspires me always.
Russell