As I start to approach 80, and likely won't be raiding, what reputations/etc should I prioritize for some pre raid BiS gear? I'm also going to be pvping eventually as well, but I feel like that gear is pretty self explanatory.
I'd recommend getting AtlasLoot addon for this purpose. Trying to remember random items from random reputation factions can be bit challenging. AtlasLoot lets you see what reputation vendors are offering at what reputation level. I'd 1st check what Honored/Revered gives. Then look for what Exalted status gives.
Generally speaking, you'll want that hit cap, or as close to it as possible.