Can't find any pictures online (and the damage was caused by demolition, not additions), but I reckon Edgware is a shadow of its original self. As built in the 1920s, it had two wings, each with a colonnade, that gave it (according to the drawings I've seen) a much grander and more impressive appearance than merely the centre section that remains. One wing was demolished in the late 1930s, as part of preparations for the (later abandoned) Bushey Heath extension; the other one (which I do just about remember) remained until the late 1980s, when it was demolished to make way for the new bus station.
On a smaller scale,Rayners Lane had its flow ruined with the automated ticket system went in (also late 80s/early 90s), leading to the closure of the northern street entrance, effectively destroying its symmetry.