I can't stand when the lights are different. Having some of the warmer white and some daylight just makes the warmer look way too yellow and the daylight look way too blue.

I would get 4000k for all.

Never use 4000K for interiors unless it is a manufacturing plant or big box store. 2700K mimics incandescent, however I find that areas like kitchens and baths do well with 3000K. If you have an open floor plan and are not comfortable with mixing temperatures between spaces then 3000K would be a best approach. My design work is all about stress reduction. Proper lighting is a huge part of what I do for clients.

I’m with reflective design- 4000 is strictly for commercial, 2700-3000 for residential. For most of my older clients I use 2700 because they aren’t even aware I switched to led that way and it will match other parts of the house that are still incandescent. My personal home is all 3000 which is just slightly whiter. The painting studio downstairs from my office uses 4000...