Subject matter is more important to me than style. Of course I am working on my own style, trying to learn technique and ways of thinking about paint-handling, but that is a means to an end. The end, being subject matter. I have the feeling subject matter will not make you a great painter, as many famous avant-garde artists of the modern and post-modern periods are using 'nothing' as the subject matter. Robert Ryman is a perfect example of this. However, what really attracts me to the idea of painting is creating a visual world in colour that doesn't parallel the real world but extrapolates it. Check this out:
Andrew Brandou, cult paintings done as a 'children's book illustration'
and on a lighter note,
Homestar runner "altered" children's book illustrations