Unfortunately all your options require custom work: It looks like you need an 18" corner cabinet. You will have to modify the last wall cabinet on the left. As I am eyeballing it, you should be able to cut the last cabinet in the middle and then shorten the left section to fit the space of the wall next to the door trim. It's an option that makes the area looks symmetric. Or you can install shelves over the sink. I would not recommend it because it will take the looks away. And the last option will be to remove the last cabinet, shorten it so it fits over the sink and install a single cabinet where the double one was. This will leave a triangle space behind the corner where the two cabinets will meet. You can block the space under it. Hope this helps!

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.

The backsplash near the hob should preferably not be glass as the heat produced near the stove causes the glass to break due to continuous heating and cooling which makes the glass crack over a few months... Pavithra Praveen Pravisree Kitchens Bangalore

It’s is back painted glass. As a back splash it can be used as it’s easy to clean and maintain. Highly recommended to be toughened. The entire back needs to be cladded in waterproof plywood and then the glass is stuck on to it with special adhesive or silicon gel. Any reservations on using plywood then you can opt for WPC ( wood plastic composite ) which is alternative to play and is totally termite-water proof.