Prefer the white cabinetry. It provides a nice contrast to the wood flooring.

IMO way too much stuff on the shelves but I would need to know hwere this is located in the house and the pics of that room .

I would paint it the same color as the walls.
Otherwise white.
And if you can, change the hardware. It’ll make a very big impact.

Ordinarily, I would say, leave it the wood color, but, in your house, I think the cream white is a very good choice, with your flooring, and also with your blue walls.

White.

White.

White, but more crisp than a creamy white. See below for another idea and don’t forget to update hardware. Last suggestion is to remove the baskets so it doesn't feel as heavy and crowded. Accessorizing can take a lot of time to get right, but there is lots of on line help.

https://www.amandashieldsinteriors.com/amp/design-guide-styling-the-perfect-shelfie

Match it to your installed white trim and upgrade the hardware, You said the magic word; bookcase! install led lighting in the shelves. Instead of using it for storage, consider decor (1/3 books, 1/3 large decor items and 1/3 open space.) Books can stand, stack lean or support other items.

It depends on the rest of your house and space. Do you have wood trim around the windows or on the doors? If this is the only thing stained, I like it painted white. Use the same white you have on your floor moldings.