Speculation: The Silence, The Girl, and Those Other Guys

Head has been entirely too full of theories and spec lately (anybody else really looking forward to the hiatus?), so here's a few strands of possibly related, possibly unrelated theories that I've had floating around and needed to write down so as to get them out and see how crazy they sound.  All of the "things are never quite what they seem" variety.

Spoilers for all aired episodes.

( Lots of stuff under the cut . . . )