I think you can get away with creams/beige. Just use some bright accessories to liven it all up. Black look fine, white could be a bit crisp perhaps.

I think the black is good for contrast amd drama. I think the white will be too safe and wishy-washy. Things always look better with odd numbers, so I would add a third matching black pendant, and a third matching black bar stool.

Black is more dramatic and creates more of a statement than classic and safe white or beige... but remember too much can enclose a space and make it look small. Ensure light flooring or a feature wall with some colour (wallpaper) to break up the monochromatic feel.

As Dr.Retro suggested 3 stools they look very comfy but not three pendants as well, you could try something long similar to the photo cheers

What about adding some colour in? This lounge is a similar shape but a beautiful rich burgundy colour :)

Stools with wood on them would help add texture and warmth to your kitchen, along with accessories like your chopping boards, maybe a fruit bowl. Potted plants with lovely green foliage would brighten up your benchtop, and a large potted plant would look particularly lovely against the dark charcoal sofa you are looking at.