HI there, Yes, our site can't upload renderings unless they are jpgs or png, so i have converted them for you..

If you love the marble tile, go for it! You can always buy a stainless or white range hood backsplash like this http://www.wayfair.com/Air-King-Range-Hood-Back-Splash-SP2430-AXK1174.html to slip in place when you are cooking something really messy. I have a travertine backsplash and use a stainless sheet when frying. It works great and no worries about stains ruining the stone.

Teal is a very trendy colour, but having it on all four walls may be an overkill in the kitchen, especially with that dramatic chevron dado tile. I hope at least the 4th wall is white! The cabinets have to be white too

You could go for tiles with design if they are simple ones. if you want plain, you can add some life in the country style with an exposed brick facade or subway tiles. for colours, it depends on how far out of your comfort zone you're willing to go. white is the safe choice, but you can go for blue, green, yellow, all pastel hues