You really need to collapse long posts like this as a courtesy to others.
That said:
I think you're missing a lot of the point of these. Each is intended to be a vignette capturing the vibe of the site, a sort of guided tour of the part of the lore it represents.
Site-77 is the heart of a fantastical noir world of atomic-powered superweapons, psychic spies, and plain-talking agents in trenchcoats and fedoras. Ergo, it is written as if one of these agents were describing it.
Site-88 is, much like the American South it is located in, a crossroads between the cutting edge modern world and things that remember days before barbed wire. Only fitting that the tour guide is one such thing.
Site-64 is a relatively young and unassuming site, efficient and laid back at the same time… but has risen to some minor importance recently. Hence, a modern and clinical document that doesn't spend a lot of time on details.