If you go for your rectangle tiles, especially with horizontal lines, they will widen your hallway x

Narrow houses are always tricky, and long narrow spaces need particular care. I think that putting the kitchen centrally makes sense, but I think that the kitchen island is far too big, and dominates the whole space. It also cuts the space in half, creating a sense of 3 small spaces crammed together, rather than the open-plan room you might be aiming for. My suggestion would be to shorten the island by 600mm, push it against the wall as a simpler run of kitchen worktop, and have a smaller peninsula unit at the living room end with space for a couple of stools. I'd put storage under the stairs, and include the washing machine if possible to free up more of the kitchen. I think an integrated fireplace might take up too much space - what about a small wood-burner instead? https://www.modernstoves.co.uk/neo-multi-fuel-wood-burning-stove.html?gclid=EAIaIQobChMIiLCc09Hj3gIVCZ7VCh1BBweoEAkYFCABEgLOCPD_BwE# You could pop it into the corner of the room and have a smaller 'floating' wall cabinet for storage. https://www.theplasmacentre.com/tv-stands-and-av-racks/tv-stands/sel-wander-1800-oak.html?cpgn=201&utm_source=products-adds&utm_campaign=sel-wander-1800-oak&gclid=EAIaIQobChMIx7e1g9Lj3gIVmed3Ch0Arw72EAQYASABEgI_7_D_BwE Good luck!

I like the second plan better but not sure the nook thing would be worth it just to get light into a utility room (if that was the intended use). Back door useful though. Architect - I was expecting mine to give me great ideas that I hadn't thought of myself. This wasn't my experience and others I have spoken with have said similar. Maybe I have watched too many TV makeovers and my expectations were too high. For me the architect was useful for telling me what I couldn't and couldn't do and what would add significant cost. I'm happy with my final design but I pretty much designed it myself (and changed it halfway though construction!). Maybe I would have had a different experience with a better architect. You live and learn.

My hall and stairs are very similar in my 1930s house. What I would do for a wider hallway! I’ve kept it simple with a stripy carpet, although yours looks fine, and pale grey walls. You coukd go darker below the dado rail but it would darken everything up which I don’t think you want. I did that with a green shade and I found it so dinghy so painted over that! However, it looks like you have better light than me. I’ve put a coat rack in my tiny hall for just a couple of coats, otherwise it hinders the place even more. I have put a mirror and some art at the top of the stairs but not coming up the stairs as again you could end up brushing against them as you go up and down the stairs. I don’t think putting a scooter on a wall is particularly decorative and would just clutter up the space.