Tries to be easy to build. Red Circuit builds are huge, because the recipe is slow, so I like to use cheap materials. The exception is the front of the build. If the full build is so large, I figure the front can take a little space to set things up.
Yellow belts are fine (and save a lot of iron), unless you build more than 5 tiles. You'll have to upgrade the yellow inserters to blue if you use faster belts.