I had black stone bench tops at our old house. My kids would sit up at the bench whenever I was in the kitchen, so I was constantly cleaning off the little hand prints they left behind which seemed to be more obvious when light would hit the bench top, but it was easy to clean overall. Just moved into a house with a white corian bench top around the kitchen sink and stove area and it shows everything, every splash, bit of dust, tiny speck of whatever, everything. Makes me miss the black stone!

I would go matt stainless steel, it will match any other silver or chrome in the kitchen (cupboard handles;tap; toaster etc). I've been looking at double bowl stainless undermount sinks and thought the Blanco essential U2 model was pretty nice (and about 788mm). good luck!

White-matte cabinets (flat panel, not shaker) and white bench (or maybe epoxy sealed marine ply??...siriuskey can tell you about that), mirror splash. Love the ceilings. I personally would go for a modern, stream-line, no handles, integrated appliances look. This space has real potential to be very cool, even with the slate. It doesn't need any more more texture or darkness. This is a nice kitchen, you should be able to sell it on ebay.

Thank you everyone for your responses. I’m still undecided - I have a few weeks to consider what to do. The bench top salesperson showed me some photos of the few people who have added a small amount of benchtop stone to add some height (and it’s always because of a busy 60 x 30 patterned tile that the owners want to keep perfect) and in her words it looks ‘dicky’. Not least because the tile sits flatter against the wall than a 2cm thick slab of benchtop. It leaves a pronounced lip of 1.5cm where tile meets benchtop addition Then there’s the safety concerns mentioned above about flames near stone which I had not considered. Big reader - I love your maths but I’m only 150cm tall. Even with a low bench and oven height of 94cm (my oven’s lowest height setting) plus 70cm of tile between the bench and overheads, the cupboards are already 14cm above my head. This barely makes them usable for me even now! Adding another 15cm instead of the 10cm, while looking lovely and keeping the pattern intact, means my short-arse self will have real difficulty reaching anything safely. Every cm counts when you’re short! But I do appreciate your input!