I actually know someone who named her kids after Zack and Cloud (because she commissioned me a drawing of them as their Christmas present, it was so sweet and heart warming!)
I would definitely named my kids after fictional characters as long they are good names and hold a sweet sound in them. For example, Zelda, Marth, Luigi, Midna, Cecil, Firion, Bartz, Terra...
I just realized I need to adopt a lot of cats and named them after my favorite characters! XD