I agree is something wrong on the art.
I like the comic book style, and I think the artist is good, but there is clearly a lack of documentation, I would say the problem is more on the art direction than the art per se, UZI on 1954? skyscrappers on macao at 50's? and many characters dress in 2010 fashion.
A real shame because IMHO pay a bit of attention on the historical setting of the art (even if the product don't pretend 100% historical accuracy) makes a very long way on the final product charm.