So, update.
The paltrok mill idea isn't going to work in Source. Too many things need to happen before it even becomes remotely possible to do it properly.
So, I wanted to do something. Made an SFM poster, uploaded it, then my brain said "hey, go sleep right now, or I'll give you this massive headache." So I slept for 7 hours, woke up, now kinda torn between leaving the jam and watching Crash's stream, or continue making SFM posters with the thought still in my head of "I wanna map".
Then, I suddenly remembered a layout scetch I made, oh I don't know, 2.5, 3 years ago maybe?, well before I joined this community. Never got around making it because of my inability to use Hammer (I had an old-ass MacBook Air back then, good luck doing anything useful on that) and because school was still a thing. A mirrored symmetry KOTH map with a twist: instead of putting the teams on opposite ends of the map, I put them next to each other (I did the Powerhouse layout before it was cool) with a mountain between them, with a train going trough it.
I have no idea if this is going to work, but here's the scetch. Then it was called Foglands, but that's a boring and generic name, so I decided to rename it to something else.
Meet koth_rockies. Will use the Frontline assets. Quick map story: RED and BLU want command over a bridge. So they have a fight over it.
ps don't take notice of the heights listed, I had no idea what I was doing back then and what scale meant.