Filling gaps between timber floor boards can lead to disaster and is best avoided. Sanded and polished timber floors tend to swell slightly during the humid months of the year and shrink again in the drier months. This creates movement in the timber floor. If you fill the floor when the gaps are at their widest and then encounter some humid weather, the floors will swell, closing the gap and forcing the filling out of the grooves and cracking the timber floor finish. This looks far worse than gaps in the polished timber floors. If you can't live with the gaps, laying a engineered timber floor over the top may be your best choice. Painting your floors white is also best to avoid as this only accentuates the size of the gaps. Good luck with your decision. Engineered timber floors

The photo below is my suggestion for colour of floor. Furniture should be darker - similar to below. For the rug - choose one colour from the artwork and find a similar coloured rug. Don't put a mantle over the fireplace - it could be a health hazard - bumps and bruises. Blinds - unless you want them to make a statement I think white - to match window frames would be fine.

Timber with timber can work brilliantly, and it's in keeping with the mid century style you want for your home. This room (below) is a little similar to yours, albeit with less of a pitch to the roof - the large feature lighting helps to break up the expanse of timber on the ceiling. You have a lovely open plan area, so I'd be inclined to use rugs to create zones and a cosy feel. Rugs reduce the impact of a large expanse of flooring material. They have the benefit that you can swap things around to change the look and layout at little cost. I think one trick may be to define your "walls" carefully, and paint these before you go with a new floor. This should give you a sense of whether the timber is overwhelming, and how to balance it. E.g. You might decide it works best to paint the kitchen cupboards to white, to give you a more seamless look and work with your new counter tops. If you want to experiment with the "paint ceiling" approach - gulp, it's a big one!! - then maybe that small section above the kitchen bench, at a different angle to the rest of the roof, could be the spot. It seems to have the same horizontal line as the wall, so even if you don't like the painted look for the whole, you might be able to get away with blending this into the walls. Best of luck!

Unless you live like animals, carpet does not 'harbour' a single living organism. It's a scientific fact. It's your bed that harbours organisms. Carpet acts like an air filter for dust, waiting for you to vacuum it out. Timber flooring allows dust to be constantly stirred up into the air in the home unless you vacuum and mop daily. At the end of the day, go with what you like- carpet in bedrooms and not in high traffic areas is logical. I've manufactured carpet for years and wholesale carpet and hard flooring. There is a lot of misinformation out there about all flooring types. Happy to answer any queries.