Also what type of cladding would anyone suggest?

~$400 including expedited shipping. My GC just had his regular countertop guy do them, which wasn't great.... he had trouble making clean cuts. If I were going to do it again I would have pressed for someone with expertise to cut them. You can see in the image that the facing is not made of the stone peak, because too much was broken during the cutting to make the mitered edge. I'm a little bummed, but mostly pleased with the surface (which is the important part) thus far.

Mod Podge is the best stuff for decoupaging. That is pretty much what you will be doing except with a much larger piece of paper. If you do this procedure make sure you coat the completed item as well, not just what you would do to make it bond onto the wood or canvas or whatever material you are using. Have fun!

I would consider something light with some other colors to mix in like this. http://t.homedepot.com/p/Silestone-2-in-Quartz-Countertop-Sample-in-Mont-Blanc-SS-Q0220/203674451/ I like the wood paneling and would paint it a white with a warm feel to it. A white will reflect a lot of light from your large window. I wouldn't paint the window casing as it might tie in better with the rest of the house. Good luck!!