One of my favorite features in indesign is being able to toggle between a work view and a final preview view that make all grids, tools, and artwork outside the dartboard invisible so that I can see how the final composition looks on the page, and I think that would be a great feature for Illustrator, where areas outside the dartboard can be a jumbled mess of old work and saved previous versions, or artwork that peaks onto the page but hangs off it as well.