Beyond "the pillars," there is no official guidance about what should be included in a BSA/AML policy. My personal suggestion is that you address each of the "core" examination topics as listed in the FFIEC Manual.
As there are exam procedures for reviewing monetary instrument sales and wire transfers, but none for the "general" record retention requirements, I would combine all three of them under the same heading.
As rlcarey implies, do not reiterate legal requirements in your policy; incorporate them by reference such as a mention of Schedule P. (Make certain that its content doesn't change as future editions are published.)
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In this world you must be oh so smart or oh so pleasant. Well, for years I was smart. I recommend pleasant.