The Silence are a cruel and callous Order who will destroy people simply because they have the power to do so.  They oppose the Doctor because in the asking of the obvious question will bring about their fall (and it really is obvious).  Does this mean that they are intrinsically villainous and evil?  They have their self-preservation in mind, not ours.

Reading the description of the final confrontation, the Eleven sounds like the Doctor himself.  I suspect it will prove to be a regeneration scene.  So there could be another season or more before they reach the fields of Trenzelor.

I have an annoyance with the re-imagined series using military personnel as mooks.  I have fond memories of UNIT from the original series.  There were re-occuring actors who played characters in their right.  Now they are just a running total of characters for target practice.  The same happened to the Silurian soldiers who supported the Doctor in A Good Man Goes To War, and with the human soldiers in the collapsing time-line.  They couldn’t defeat the Silence, but Amy could, shooting them in the same way!  Inconsistency?