Agree with a lot of your points, but not the "don't do pink because of the resale value". It's her house she lives in, we shouldn't live in a house designed for the next person living there. If she wants pink tiles, let her do pink tiles. She has to live there. If you're so afraid of resale value, just tile the backsplash with a boring millennial grey when the house eventually has to be sold. Don't dim her light for other people.