I'm working on a set of choropleth maps for planning project areas. We're discussing whether it's better to create maps with percentages of total population or to show density (normalized by acre of census tract) of percentage of population. The maps are just to show where the planned project areas in relation to areas below poverty, etc. are. So is it better or more of a standard just to show where percentages of population demographics are or would it be better to show the density of those areas?
It really is completely up to you. Try it both ways and see which one you feel shows the data better. It is hard to visualize what you mean, because at first I would assume that either way of showing the data would inevitably produce the same end result. Larger percentage of the population would be the same as higher density, and lower percentage would be lower density. Unless you have something more specific in mind, I'd say do whatever makes the most sense with your data.