Help Designing Montoya Family Mansion?

I'm slowly working on building a mansion for the Montoya Family. I based it off the main floor plan here: https://www.houseplans.com/plan/2373-square-feet-4-bedroom-2-5-bathroom-2-garage-european-contemporary-southern-sp216857

Anyway, I can't decide what to add later on.
I built on a 64x64 lot so I'd have room for a large backyard.
I made a nice wraparound porch instead of a front and back porch.
Juliette - Artist - Daycare Career, wants to become Private Investigator.
Valentina - Singer Career - Wants to learn every instrument.

Should I add, and how:
Art Studio - Easel, Sculpting, Inventing area
Music Room - All instruments
Movie Room - Big flat screen tv
Gameroom - arcade machines, foosball, pool, basketball machine...