In reply to hpil:
Second vote for Cummingston, From memory, Primrose bay near Hopeman has an undocumented slab giving good Mod-Diff lines that might fit the bill.
Just checked the NE Outcrops guide, the Primrose bay slab is equipped with stakes to: "allow convenient top roping for youngsters or non athletic novices". Easy to combine with Cummingston which may be a bit sandy.
Post edited at 17:54