Your mockup scheme is similar to our master bathroom we just completed - photo below. I know you mentioned storage being a concern - our mirrored cabinet has offered an amazing amount of storage in a very small space and also helps bounce light around. I was worried about black taps etc too so we kept chrome fixtures but added in a matte black candle and black potted orchid to create a similar effect which we can change out later on. Our floor tiles are dark but because they are semi-polished they actually bounce around a lot of light and don't make the room feel dark if that is a concern. We also have a huge fiddle leaf fig in the corner (not pictured) which adds a really nice feel to the space - a plant like that could help bring in the outside greenery in your bathroom. Instead of the storage tower you have to the left of the vanity could you do say some floating wood shelving, possibly with baskets added for more hidden storage? You could also bring in the 60s theme with what you displayed on there eg. photos as you mentioned? In regards to the window - a previous house we lived in had a window at about shoulder height in the shower - as well as letting in heaps of light it was amazing for storing toiletries etc!

Is your final photo of the vanity you already have? I also thought adding legs would take it back to the MCM you are after. Would be interesting to know how the silver drawer pull is attached. Not sure about painting it matte black as I thought timber furnishings were more prevalent then, but it's totally your choice. I hope you will post updates as you go. I just love mid-century.

Oh this project grows. I’m thinking the kitchen/laundry access is probably worthwhile (light, access, etc). I’m liking the more contemporary layouts, compared to the u version that I liked at an earlier date. Siriuskey your comments about that version being too wide were important. (I eventually remembered design issues with my mum’s last kitchen which was a u and too wide and while it felt spacious, it was a bit ‘not quite right’). oklouises’ wed 5.26pm (2nd option) is probably my preferred option at this stage. I think that would be functional and satisfies my wish list pretty well. Layout and furnishing the greater space is still on the go. I must say, I’ve found everyone’s input with this project so creative and helpful.

Personally I love angles & splays, BUT they have to have purpose and be functional. Without seeing more surrounding context hard to comment but i can't help wondering why this all being so squeezed in one area, but then almost wasted/under-utilised space in-between the island and the table - it's like the pantry's boxing/internalising the kitchen which is not ideal.....either way I'd make sure that it flows and is functional and not awkward anywhere