It's true that tools and materials are expensive with woodworking, but I end up designing a new piece of furniture (pretty much variations on a box) maybe 1-2 times a quarter. I'd much prefer using a native desktop application over the clunky web-based Sketchup UI, but at ~$33/mo it just doesn't provide enough value to me as a hobbyist.

KetchUp/BenchUp seems promising -- I was able to import a file from Sketchup Free and navigate around, but the polish just isn't quite there yet. This should improve quickly I think.