The way this art is colored and shaded, with the lame gradients, airbrushing, misguided attempts at making things look 'shiny' and and generally bland and inorganic color choices... it all makes me think that the artist(s) responsible failed to understand the appeal of One Piece. The tone of this art is too generically 'badass' and not silly and adventurous enough, and even when judged on its own it looks shitty. It's also funny how Ace's boringly-drawn flames don't even give off any light.
Compare this art to the far less detailed yet also far more atmospheric art in these screencaps http://www.awesome-engine.com/wp-content/uploads/2009/12/onepiece.jpg where the colors are carefully chosen to depict a very specific mood.