Wouldn't it be more comfortable to lean back into your harness and sit during the belay? That stance seems like a killer to the neck and lower back.

Definitely sit and build the anchor over your head!

If I remember correctly, there isn't much available above his head, particularly due to the rock quality.

I think the best thing to do here is as Dave says and belay 20 feet lower and then link the next 1 1/2 pitches to the top.

Yep. The classic Eldo "I think I will try to make it to the next ledge, damn I don't have the right gear and this sucks, now I am going to downclimb to the last good ledge" sort of deal.