there is no perfect dimensions for an island. Try to organce space subdividing into smaller cabinets of 60x60 cms which is the max space for a structural division and works for seating area as well

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.

Your choices don't flow well to me. The flooring in your photo is pretty (very dark...are you okay with it showing every footprint, smudge, and dust bunny? If so, that's fine). From all of your options there I would do white cabinets with the Himalaya White granite. But you said ignore the granite. :) I would go for the gray cabinets with white quartz everywhere in that case, but personally I'd worry about gray cabinets being very dated in a few years. Is there another quartz option that you could pair with the white cabinets that is light in color and maybe has some movement, like LG Bianco Drift?

I have used both with good results. The main difference between Quartz and Granite are 1) price, 2) colour range. Granite generally works out cheaper, because you can buy the exact quantity you require. Quartz comes in large slabs of specific sizes- standard size being roughly 10'-0" x 4'6", so there tends to be more wastage if you don't plan the cutting well. But Quartz is pretty and comes in a wide range of colours and can be re-buffed at a later date. Quartz also comes in various thicknesses- the most commonly used being .75" to about 1.25". And especially when you use dark wood cabinets in a kitchen or bathroom, beige and white counter tops work very well. Some people go even with coloured counter tops like blue, orange, yellow. Natural stone in light colours tend to be porous and stain easily, so I prefer to go with pure black which is safe.