There's a little track that's near me, very hilly, very challenging and I think it would transfer over to LFS really well. The one thing that would be a problem is getting the permission of the group that runs the track, to recreate it for a product that would be sold - I talked to them about making it for GPL and they didn't mind, but for LFS, well...
It's 1.6 miles long, 12 turns and near 100 feet, if not more of elevation change