I would actually try a glossy black, or perhaps a japan black stain with teal scatter cushions over your neutral cushion. Glossy black looks great against blues and green, its a simple classy look and its easy to change it up with scatter cushions should you decide to use it elsewhere in the house.

It may have something to do with the cold, but they do look like they are missing an element, try Epsom salts diluted in a watering can, then in spring either re pot or add a small handful of dolomite lime ( try just one pot first) to make sure it doesn't take them out, definitely reduce your watering so, your potting mix is probably leached of all minerals, do not fertilise until spring

That's a good question! Unfortunately, it is difficult to say as it seems that shedding depends on the type of bamboo you get. You would be best of getting professional advice on what type of bamboo would be best suited for a pool area. It may be the case that, if you are looking for very low maintenance, bamboo might not be the best option in this regard. Here's a link with a number of comments on this topic which might help: http://forums.gardenweb.com/discussions/1743451/bamboo-around-pool

I would paint the wall with Bulls Eye 1-2-3 Primer made by Zinsser which can be painted over any type of paint without sanding, just a wash down. See before and after photos of what I did over 10 years ago when faced with timber panelling in a few rooms.