When I was at school in Devon England, I was taught: I shall, you will, he/she will, we shall, you will, they will. If they were reversed it was to create emphasis: Oh no, I shall drown! (accident) I will drown (I intend to do it and you cannot stop me). The fact that I am a native speaker and did not know this suggests its current usage, or lack of, in modern English. As it is nearly always reduced to "I'll" or "we'll", I don't think it matters what you use. Back to the sentence: we will never be silent/ we shall never be silent - both should really be accepted. Any comments?
In America, my teacher said you only use 'shall' in writing, and never when speaking or people will think you're insane. I think will sounds better for spoken language, but if you want to sound formal when writing I think shall is okay.