I would like the notion of the intersection reversed. What I think would work better is have intersections act as spiders that you can pull a corridor out from each leg instead of bringing your road corridor to meet the intersection. If you have 5 lanes to the east tell it that and have targets set for when you pull off the road to the east with your assembly. Sorry it is hard to describe but intersections are the core of what we do.
Also give us a join corridor command. There are some pretty smart people at Autodesk maybe they can take a look at this.