The Numinbah valley road is one of my all time favourite rides, and I think many bikers in the region would say the same. I moved to riding in Northern NSW for most of last years in the area. I liked the scenery and roads better and QLD had become too anti motorcycle.
On either side there are countless good roads but on the southern side you can detour via Tyalgum for great views of the caldera and a nice small town where there is good food and a friendly pub.
I have removed the original post as it was too old, please see the map for location of this road.