I really like the look of that kitchen. There is really nothing like natural stone and marble for beauty, that splashback is kinda like a piece of art. I guess you would want to keep your colours and design simple so it doesnt compete with the marble splash. I dont mind the two different materials, mixing engineered stone on the bench with a feature marble. You really would have to choose wisely though.
I'm getting a grante benchtop with waterfall sides on the island and was a bit scared as i know granite can stain but its so lovely i just went with it over the more stain resistant engineered stone.
I also tested a sample of the granite with red wine and it was ok if cleaned up quick, leave it for a few hrs- not good. I think marble is even more porous so i would be very careful if making a messy bolognaise sauce esp with a light coloured marble.