Scarif plan flawed from the start
Given that:
1. The Stormtroopers are utterly ineffective in this movie. They don't even bother to stand back and shoot the Chinese man with the stick, opting to run at him one at a time so he can easily defeat them;and
2. Fanboys on Earth can make the armor in their garage
The Rebels could have gathered enough armor and other Imperial uniforms to put on BEFORE they infiltrated the base they had to steal the plans. "Just start blowing stuff up so they'll instantly know what we're up to" is not smart at all.
http://www.youtube.com/user/patbuddha