I agree that it can be upsetting at this stage but your timber will all darken naturally and the difference will become less obvious over time and once you have furniture and rugs in place it's likely to be one of those issues that only you and no one else will notice. And I defy anyone to not have something like this in their house which has been newly built/renovated. I know this isn't terribly helpful but I don't think ripping anything up to start again or going to great lengths to seek recompense from supplier/installer is going to help your blood pressure either (by all means raise concerns with them and ask for suggestions from them).

Hi there, I will suggest you to think about natural wood or oak color, we have both of color in our warehouse, welcome to here to select the timber and color.

the range hood can't be timber but a standard range hood can be built into a frame that can be covered in timber.. research suitable built in range hoods and then discuss with your kitchen cabinet maker

You don't match your walls to your floor but to your taste. What colours do you like? The nice thing about timber flooring is that it's neutral. It goes with everything.