I've bivi'd on a wall sort of like that in the NWT of Canada. Even met Gordon Wiltse [the photog] on that trip. No, Gordon wasn't our photog, nor was our climb as hard as that one on Great Sail Peak.
Water. Water is going to be your biggest problem. IIRC, we had 63 liters of water between the three of us for 6 days. The haulbag containing the water weighed as much as I did, and the only way I could haul it was to invert myself at the anchors and push against the anchors with my feet whle facing towards the ground; my body weight alone wouldn't cut it with a 1:1 hauling rig, and rigging a 2:1 just took too long. It was a pretty miserable day or two of hauling until we cleared the lower slabs and made it onto the steeper headwall.
Water is also a problem when you get hit by a storm. I was surprised by how much water a snowstorm produced on a wall like that. The ropes get soaked, and eventually those fancy rianflys start to wick water into the middle of the portaledge. The guys a few miles on the other side of the ridge from us got hit with 17 inches of snow one night. I think we only got 4 or 5 inches.
It was a constant struggle to stay warm, stay dry, and keep from burning everything to bits with the stove at the end of the day. Nothing says excitement like a boiling pot of water hanging above your crotch.
If you could suppress your fear for a minute, and take in a deep breath while way out on the lead end of the rope, it was a magnificent feeling to take in the view.
Gordon makes a mention of Galen Rowell and his Mountain Light Art Gallery. Here's some of Galen's work...