I battled with the Civic Society for a plaque to be put up for Marie Longmore and her husband, Frederick Humphreys, at the site of their home in Wheeley's Road, Edgbaston. She was a well known Victorian actress and singer, her home theatre being the old Theatre Royal. He was the musical director at the same theatre for forty years. The response I got back was that they weren't well known enough, but I have well over 300 newspaper reviews and Marie performed all over the USA as well as the Haymarket Theatre in London.
A friend of mine, who was the producer of many shows for the BBC, said "I bet if you put the cash up front, the plaque would miraculously appear the following day!". Cynical maybe, but I've never heard of many of the people named on existing plaques either.
Maurice