This thread struck my interest. In regards to uniform "change," I think it's those that had minor, moderate, or little tinkering/alterations here and there were and are far more respectable than those with radical, space age, and those that claim to be for "arts" sake (do me a f***ing favor).
Those that have done quite well with their slight changes have been SCV, Spirit (minus the '88 and '89 years), Boston Crusaders, Garfied (CofBC, Cadets, or whatever the bloody hell else you want to call them), and the list goes on.
Some corps that "think" they are on the right path with radical change not only chase away alumni; but they do little in the way of member retention and possible recruiting. The only two corps that I have seen do well with radical uniform changes were the Velvet Knights and Star of Indiana; however, they were also theme corps, so there is the answer.