Custom Interchange: Overpass/Underpass with roundabout. This may seen a bit of a low priority idea but I'll put it forward anyway. A ground highway perpendicular onramp for avenue, but instead of the avenue going straight across the top with turning crossovers, there could instead be a roundabout on top, with the four arms of the onramp making up the parallel routes, and the avenue the perpendicular paths. This could also be adapted for roads with a smaller roundabout, and foir elevated highways with the roundabout underneath the highway. It's more of an aesthetic idea, but It would go nicely with the avenue roundabouts if and when they are completed.
