Adding the floor level bit
* '''Coloured wool for navigation.''' The previous navigation of coloured wool paths leading to arches with main roads works very well for new players, and gives roads visual distinctiveness. So I'm suggesting that we colour each road and its archway with the seven colours of the rainbow plus one, starting at North and working clockwise. The combination of the colour wheel and the compass could work well as a mnemonic - if you see at-a-glance that you're on the green road, you can "count" clockwise from North/red and work out that you're on the South-East path.
* '''A new, square hub''' to fit the new rotationally symmetrical road system. To make sure it's navigable and difficult to get lost, I've added coloured posts with signs to match the corresponding archways - and there will be other landmarks such as a horse pen and a small family of mooshrooms for easy food. Players will be able to add signs to the coloured posts to indicate which is the best road to take to get to their builds.
With the evenly-spaced main roads, I think it will be less work in the long-run getting new people connected to the network.