Biddick Woods has had a number of commercial services, normally the Houghton - Newcastle services, which at one point worked on a 30min frequency (x3 and x4). GNE axed them and now Nexus have to fund the hourly 37.

I get what your saying about Teal Farm. At Elba Park there is/was plans for a pub too (not sure about the retail units though).

As for Birtley, the 23 used to run to Malone Gardens - that was all changed just as the new houses were being constructed.
I do believe there is some sort of Taxi Bus, but it only serves a small portion of the estate.