Hey ascanius. City is below, and yes it would. I am still on the fence about whether I want to extend the wall.
Walls are sometimes more than just defense from invaders. Sometimes it's more about control of economics/trading/merchants and such. Or thievery.
Sometimes it has to do with controlling the population inside the walls.
The expansion was done by a force that invaded and subjected the original population of Haerlech.
That being said, like I said, I'm still on the fence about that area of wall. And a few other spots. It's a WIP so perhaps it may change.

I thought I'd add, the invaders are the only real force in the area that pose a threat, atm at least.