I’m going with an ink on paper (recycled, ‘bamboo’ colour) visual style, and I’ve just got a title screen up and running:

I wrote a wee command line app to take the greyscale ink jpegs from my scanner, and convert them into RGBA pngs with the inverse average of the RGB components becoming the alpha channel (i.e. any white spaces in the original image are made transparent).  This way I can just draw the ink images on top of the recyled paper image , and not worry about the (white) paper I did the inking on.