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.

To Modernise this without rendering or retiling the roof I would probably recommend to go darker with the trims. My top pick as a colour consultant would be Dulux's Domino for the trim. It will be a little bolder and create a more modern contemporary feel. You can see it pictured below as the trim. Obviously this house has painted their bricks in the shade "teahouse" however it will still look much better on your 1980s "peru" colour bricks! Don't hesitate to contact me if you need any more help colour wise!

Do you have any furniture you are wanting to put in there ? Does any of it have any colour ? I like the light floor colour , the rest let's just say it is a good neutral base . I'd start with a new front door -- a darker varnished ( glossy ) wooden door , or possibly even a blue to reference your outside . Then add colour via furniture ( or at least cushions ) , rugs , and artwork . Again , maybe several different blues would tie in with the floor , but also the exterior . If there are only blue exterior highlights , you may want to go for warmer colour inside -- reds , yellows , oranges -- again , ties in with the floor . To this end , I can't understand why people go with 117 shades of grey and offwhite and wheat -- live a colourful life is my attitude , as long as it is themed haha !

I agree with Jan -- a lot is personal , and your lifestyles . You say neutral colours , so a wheat type colour for the carpet is a good middle of the road choice , but maybe not practical with kids who like crayons and facepainting and stripping down motorbikes haha . So in that case , maybe a burgundy or mid blue or similar 'solid' colour may suit better ( burgundy may tie in more with the exterior tones ) , but is still sort of neutral , but what about furniture and linen and artwork -- if you have royal blue or fluro green drawers and a brown chair and sunshine yellow duvet/dooner cover , and the room is for someone older than 4 , then burgundy carpet mightn't be the go haha . The existing wall colour works with most things , you can add artwork or posters or sports or academic certificates -- maybe back to front , but I'd sort out everything else ( carpet , furniture , etc ) before deciding on a wall colour , unless sticking to the existing or similar colour .