If your chosen themes accommodate one another, you can create a unifying theme. Look at this: your spouse wants an Asian theme, your teenage daughter wants a gothic theme and you want a tropical theme. In such varied combination you may opt to do an around-the-world theme within your living room; this is sort of a miniature version of Disney's Epcot. You may incorporate Asian tropic samurai, dragons and plants swords that would incorporate all three themes. The thing is, regardless of the themes, there exists common ground can be found.