mapping and story

I think just having little tidbits being found by the player themselves is better than pushing it in their faces. Kind of like how Decoy did it, you can find how Soldier got the area in the first place (That may be a bit of a bad example since it's MVM with down times).

Well, the game is a multiplayer shooter with no story-driven campaign of any kind, so players are gonna expect to fight without paying much attention to the tiny details. You have to be careful with tiny details too, because a handful of people turn off decals and decrease texture resolutions in favor of performance. Whatever story you tell, it'd have to be something big and obvious that the player can glance at while running or fighting. You know those slower moving theme park rides that tell a story as you ride through them? I think those are a good example. Sadly, I don't think many who play this game wants to stop and think about clues. Players will always spawn with a gun in their hand so they'll shoot first, inspect small clues later.