In hardcopy I prefer a 10-pt font if possible. On our most recent project there was so much input that, even after cutting a lot out, I had to make one large section (the NPC stat blocks) 9-point in order to bring the product in at the budgeted page count.
I usually print my PDFs on a laser, so again I am happy with 10 pt. I get unhappy when I get something I have paid a lot for, and find the text not only very large, but also spaced gappy. As a page layout person, I prefer to keep things tight but readable.
As far as artwork is concerned, I'm all for it so long as it actually contributes something -- tells a story or illustrates a point or helps to set the theme or mood of the product. I don't like shapeless blobs. My current favorite kind of illustration is street scenes, so I can get a feel for a culture. Character illustrations are also good, giving flavor and setting to a product. I like having something I can print out or copy and show to the players and say "This is the guy."
Art that is just there as filler, not really lending anything but borders to the page, is a waste of my money.
HermioneO