Hi, Rusty!
I think most probably some - or even all - of these places originally belonged in other counties, rather than being "lumped" in Greater London.
I don't know Waltham Forest, but Harrow used to be in Middlesex - which in itself is now in dispute as a county!
Richmond was in Surrey. and Dagenham so far as I know is in Essex?
As Dagenham and Redbridge are a joint football club, I would assume that Redbridge too was/is in Essex?
(I am sure someone will correct me right if I have this wrong)
Why territorial boundaries need to changed, I have no idea!
All it seems to do is annoy the residents!
Take for example the not-to- be- mentioned disputed border territory between Lancashire and Yorkshire!