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It's important to us that players get lost within the ghoulag and freeze to death.

That's a good reference, I'll see if I can make the guardhouse area look something like that. For the rest of the map, it's important to me that it stays colossal and esoteric as it is.

Thank you for the comment!

Hey thanks for the help. I'm aware lots of locations are missing and some areas of the map are still inaccessible.

The concrete and metal is an artistic decision as this map is being made specifically for a roundbased roleplay gamemode where you attempt to survive a round in the ghoulag as a guard/prisoner that is still under construction. The plan is to have a lot more snow on the map, though it's important to me that the main geometry is made up of metal plates and the concrete pillars beneath them.

The grate road is the main road and serves as a connector between the two present villages, where the guardhouse is and the entrance. Besides this I plan to have cleared paths in the snow to guide people between less important areas.
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A decent start, but I have a few critiques:
It'd be better to use snow and ice rather then metal and concrete.

Your structures look decent, but some would be physically inaccessible. Add roads and paths to guide players. Also don't forget to use func_precipitation to add falling snow: https://developer.valvesoftware.com/wiki/Func_precipitation

I'd also suggest reading up on soundscapes:
https://developer.valvesoftware.com/wiki/Soundscape

I'd suggest starting with an env_soundscape with "d1_canals.util_windgusts" and further using this list: https://developer.valvesoftware.com/wiki/List_of_HL2_Soundscapes

As a general tip for designing maps, use real life references. The layout of the real life gulag "Perm-36: https://www.uraltourism.com/image/excursion/Perm-36/map_b.jpg

Your layout hasn't got any locations that would realistically exist in such a location, no prisoner bunks, guard areas, kitchens or even stoves or boilers to keep people warm.

We sent all the ghosts to jail