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!

I looked at the brochure but I could not find exactly what color or pattern Caesarstone has in India. I'd like the look of a "marble" Caesarstone for the counters and the back splash with your blue cabinets. I don't know if this is possible, though. I have granite in my kitchen and I the have counter and back splash in the same granite and I have loved it for 15 years. Do they have induction cook tops in India? They are wonderful, too.

I'd put in a tile backsplash. Stick with a solid color tile so your bottles won't get visually lost. Solid color doesn't have to be boring, look for interesting shapes or textures, and play around with different colors of grout to make a statement. The one in your picture looks very similar to the 2nd picture below.

quartz is a man made product using natural stone and a resin material. No sealing and is stain proof. I have had my granite for 10 years. I have never had a staining issue and set hot pots down on it seldom, but it has never bothered it. I've sealed it maybe 2-3 times over 10 years. granite really doesn't stain. So, compared to quartz, they are very similar. It all comes down to what you like the best.