All of the Halo maps in multiplayer function as in-universe settings and locations, even before Halo 4. Lockout was the site of a Flood containment/research facility used primarily by the Monitor, hence the teleportation grid would be favored over physical travel routes. Blackout on the other hand, is much harder to justify as a real location because Forerunner geometry makes little sense in the context of human design. It's supposed to be a weather monitoring station, but it clearly doesn't look designed for practical human use. It's easier to explain Forerunner design elements meshing with multiplayer design elements because they didn't operate like humans do. Lots of hovering and teleporting and all that crap. Generally, the human maps are a little more practical and believable with exits and entrances in reasonable places, even if the geometry is made for seven foot tall super-soldiers who can jump fifteen feet in the air, but it's not an exact rule.
I've actually spent a lot of time pondering the artistic/logical elements of Halo maps. Halo: CE is certainly the weirdest in a lot of ways, with spaces that lack context or even cohesion (Boarding Action makes zero sense) and then they get better at that with each game. Reach is easily the most grounded in its maps since all the launch maps barring Forge World were implemented into the campaign, but even they seem slightly out of place and had adjustments where needed (see: no air lifts in campaign. Ever. A little jarring when you get to Reflection and there are corners that serve no purpose).