Not necessarily. Just make sure they don't compete with each other and keep them very simple in color and design

I actually think all same cabinets, tile and counter in kitchen and two baths could almost seem cheap and not custom (even if they are nice finishes) - like there was a sale on "xy and z". I'd rather see them complementary but different. If you're worried for resale keep them neutral.

No not at all.

When I built my house I used the same kitchen cabinets in my master but you would never know because they have totally different tile etc. it was just cheaper to go that way as I got a better deal. Non issue I the other two bathrooms because I used pedestals.