Change out the lights to a 4000K LED bulb, that will reduce some of the overall yellow hue.

This is a big one. do this before picking any colors or bringing home samples. your current lights are making everything look very warm.

Look at Coretec Calypso Oak Pro XL. or something in that family.

You want an LVP that doesn't have a lot of grain movement, but is a warmer color. It could be dark or light, just no gray tones.

why not go w/engineered oak floors? These cabs have a similar hue (and blue gray is a great color that works with it) maybe Pale Oak for the walls, Simply White for the trim. medium stained oak floors, a nice runner. White quartz countertops, white tile splash.

Similar kitchen that another poster on here upgraded. natural red oak flooring is the best match for your cabinets. And, they hold their value more than LVP.

The cabs look like oak that have had a clear coat that has yellowed over time. If they were stripped and stained again, they wouldn't be as yellow.

Like these:

What countertop is he getting?

Hardware? If he did a nice pull/handle in a matte black/gold or silver color, it would update it.

lose the granny valance and do a nice woven wood blind.

oak cabs, white tile floor, white countertop, ORB pulls, natural woven light

it's not difficult to remove the center panel on a few of the doors and add glass to it. It can be any type of glass. it just gives it a nice look.

Here are some oak kitchens that have been updated. look at everything done

silver handles and Leathered Gray Steel Granite. I'd do a larger size subway tile

when he is ready to paint, build some boxes on top so that you gain more storage and it looks better

if he did want to paint, here are some options