The hair probably isn't but it felt weird. Like it's making a point that will need to be rectified later.
Roger is the son of one of the families in the cave. I can't remember the guys name - he's mentioned as an aside when they're introducing people. He's the son of a Jordan roofer and Ma thingies cousin.
I'm sure you're right about introducing new characters etc, and also about the weariness of the journey. But I can't help but compare it to Northern Lights with the journey in the North.
I'll probably read the full trilogy when it's out but I just wasn't that impressed. It felt like it ran out of steam.