I have finally received a reply to my suggestion that TfL need to install a pink route validator at Surrey Quays. Whilst not promising anything specific, it does appear as though there will be some new opportunities to avoid zone 1 in the new year. Here is the reply:
Thank you for your suggestions.
We are currently planning to make more routes which avoid Zone 1 available, by installing further pink Oyster Validators at certain interchanges. Please understand however, that this is a large undertaking which involves making physical changes to our network and systems, as well as producing new documentation, training our staff, and so on. It is usually the case that any major changes of this kind will be carried out in conjunction with other changes, in order to minimise travel disruption.
While I don’t have any confirmed completion dates for the works mentioned above, I’m confident that several new cheaper routes will be available at the turn of the new year.