Ok so depending on floor colours and overall look that she is going for I think (if she is really adamant) that the blue could work if you change the Amaro cabinets to a whiter shade - this will give it an overall crisp, oceanside feel with the warmth of the soft walnut. Otherwise I would contrast it more with a mid-tone colour splashback in grey/brown tones. Again this totally depends of her tastes... Here's a photo that you could show her with the blue splashback - granted it is a little deeper than her selection but at least she can see it on a realistic scale and of course the timber/white cabinets are flipped in this one. Hope some of that helps!

Looks great from what is shown, but could you post a photo showing the whole kitchen please? I am having the same dilemma and very keen to see more of your tiles.

Your kitchen is small and already quite busy. I would make it as simple and clean as possible. You can't beat ceramic tiles for cost, durability and ease of installation. Have a look at Johnson's Spectrum range to see if you can match the green. https://www.johnsontiles.com.au/product/spectrum/?utm_campaign=1602072422&utm_source=google&utm_medium=cpc&utm_content=304640004469&utm_term=&adgroupid=61761480198&gclid=CjwKCAjw_YPnBRBREiwAIP6TJ0idAicM8vfEevC-WrwRVNmbtUPHfDAjvNpkaOIo0hzN0dwMw9u1rxoC0VkQAvD_BwE You will get a neater finish with ceramic tiles than you will with trying to work with DIY stainless steel, particularly around the edges. There are lots of online resources to show how easy it is to lay smaller ceramic tiles. Leave the large format porcelain tiles to the professionals. Best of luck, Dr Retro of Dr Retro House Calls

Hi Mc10. I bought the Calcatta subway tiles on a mesh and will use this Lithofin MN Stain-Stop Tile Sealer once every 3 years. I’m still in the middle of the kitchen reno but got my marbles and they’re exquisite. https://marbleceramiccorp.com.au/lithofin-sealant-germany/1026-lithofin-mn-stain-stop.html?gclid=Cj0KCQjwr-SSBhC9ARIsANhzu16AK7RpYQb4yMtmHougfhBuuiyMAu930aAIj-0gu55tx1mM4dc-IOkaAr-ZEALw_wcB