While I personally despise pattern paints, I do like the concept and love the art in this. Perhaps thin out the amount of decals to make the placement look more deliberate? This is a very personal opinion though.

Also I feel that the black is a bit too saturated in comparision to the "concrete" grey (emphazising the concrete aspect of the grey even more would be great!), perhaps two different shades of darker grey would be good? Or swapping the black and grey parts while making the black once again, less saturated. Hmm.

Ah, I like this one a lot