I would make them all white. Before buying more paint what light bulbs/fixtures do you have. You can change the appearance by changing the light bulbs. For a less yellow look buy bulbs with 5000K color temperature

A second option is to paint just the top ones white and leave the bottom wood. You can also replace or paint the backsplash white

I think the cabinets look white, but, that yellow backsplash is throwing everything off. I also recommend that you change your lightbulbs to all led daylight type bulb. I think 5000 might just be too bluish white, but 3000-4000 should be perfect.

To soften the black you can add a black/white striped runner https://www.allmodern.com/rugs/pdp/mozingo-hand-knotted-cotton-ivory-black-rug-a000675743.html

Or thishttps://www.amazon.com/NANTA-Striped-Washable-Outdoor-Farmhouse/dp/B07XJZH6WX

The outdoor rugs are easier to maintain. Alternately depending on your style you may get a vinyl mat

https://locusvie.ca/collections/floor-mats

What size/layout are the black floor tiles. If the tiles are not too big you can add texture by painting the grout white here is an inpo pic

Sorry, here are pictures before I started priming. I thought about doing everything white but I feel like it would be too black and white and wanted to break it up with some colour. Yes, the backsplash isn’t great I know. I don’t want to have to paint to tie them in so I was hoping to find a white that would contrast them. I could paint them in the future or put stick on tiles over them.

The floor tiles are square and are 1 ft x 1 ft. Grout is a good idea but they are gold flecked... does that matter?

The lights are halogen and are about 15 years old. Is halogen not better in terms of lighting then LED when it comes to colour?

I tried white Dove and simply white but find them yellow. The whole reason I wanted to paint the cabinets is because I hate the yellow in the wood. Do you think Oxford White could be a good choice? I don’t want a stark white but do want a soft white but no yellow.