You picked a good subject to do. lots of geo to mix it up good. I do like how you made the folds inthe bags and the play of light and dark, your light source is good. I wonder though should the middle open bag be darker because it is in the shade of the front bag which in the side folds has a much darker shadow then iut goes light again. don't be afraid to darken the outline of the opening of the middle bag.. same as the side fold of that bag. all should be in shadow.. I would also brighten up the edge of the table to about three shades darker than the side of that box. I find it useful to squintt and then I can see where things might be off and adjust them.. Hope I was not to hard on this.