I’ve seen similar panelling strips at B&Q and other diy establishments. They are usually displayed in cubby holes lying flat, so you only see the end shape, if that makes sense!

OK, just take the panelling round the walls but leave the chimney breast free. You can make it a feature/focus with a bold colour. Or paper/paint it the same as above the panelling. It'll look wonderful like that, I would agree though taking it over would look weird without a surround.

Hi thanks for comment, it’s same company designing and fitting so there wasn’t a showroom as it’s a small local business. Just wondered if it will look odd to have a navy panel then the quartz waterfall end or if this is usually done like this in designs where there is a breakfast bar then a fridge or other cupboard in the island. They said that it’s done as there are panels next to fridge and so it balances it out having them at ends if that makes sense

Normally it’s around 1/3 of the wall height, maybe fractionally higher. This image looks good Most of your imspiration pics have wallpaper, would you consider that? Coving may look good depending on the style of the house, I don’t think it’s necessary in a loo though How do you intend to deal with the boxing in of the pipes? Could you increase the boxing in so it’s the width of the wall (hopefully!) just above the sink? You would then create a shelf for things, this is the best pic i could find minus the white sill!