Yes very happy i went for bold. l feel like the hearth needs balancing out on the other side with the log basket but wasnt sure what....as it would have to be non-combustible ideally!!! or would it look too busy with something else anyway?

Wow, that’s going to be a very dark kitchen. I think you will need most of those downlights, plus under cabinet lighting. Be careful to choose warm white 3000k or even very warm white 2700k to avoid the operating theatre look. Also presume you will have dimmers. Make sure you have several circuits so you can have some lights bright/some dim/some off. For example you could have the downlighters on one circuit and the the pendants and under cabinet lights on another, so you can have just the latter on when you want more evening atmosphere. Then the dining area and sitting area lights should also be separate circuits. Also consider a feature wall light in the under stairs space where you have the open area. And/or under breakfast bar lighting, or even plinth lights if you like that look (I’m not a fan personally). You are going to want a lot of layers of light. As regards layout I would suggest keeping the down lights along either wall where they are but playing around a little with the two central rows of lights so that they are more staggered and more random. Consider where you actually need and want them - eg one or two over/very near the hob (if your extractor doesn’t have built in lights), also above the prep space to the side of the hob, and maybe one just beyond the waterfall end of the island to light up the marble. Even just staggering those two rows so they are offset from the wall rows will help a lot with avoiding the grid effect. Electricians will go for a grid as it is much easier!

Yes, it is very white - it has photographed very stark - but as you have indicated you like color, am wondering what color you have in your furniture? The photo's show that the blue rug and color framed prints stand out brilliantly against the white, so thinking you may find your furniture brings in color. The white does seem to help the kitchen at the end get some light, rather than being a dark area. It might be worth getting your furniture there to see what it does in the space, and then consider your wall color. You may just need to go for a warmer white to soften the space.

Have you investigated the state of the stairs under the carpet? If they are decent, exposing the wood stair might be a possibility. If so, a warm or dark finish against a crisp wall. If you prefer to not have the noise of foot traffic, a runner with only a small margin could work. You might be able to work in a natural finish rail , or rope and wood combination rail as am thinking any rail would have to be flush to the wall so as not to encroach on the passage. The expanse of wall - hmmm. I think i would leave the walls at the side ornament free, and just paint. But the window wall could make a great gallery wall... pictures, mirrors (antique styles or interesting frames), narrow shelves for ornament/ books, or those ikea picture shelves so frames can be rearranged or updated. You might even consider a hanging - a tapestry or a drop of material that you find attractive. The hanging might even inspire your color choices. It may work to use only the upper section, leaving the lower section clear to walk through or the space may even allow for a combination of these suggestions. Enjoy exploring the possibilities!