2) Accessories can become a real problem in a kid's room, especially a girl's room. Hair accessories need a place to go because chances are they are going to multiply! You can attach hair ties and pony tail holders to a hook or series of hooks. Barrettes can be hung on a ribbon in the closet. You can sew clips onto the ribbon to hold odd shaped items, like headbands. Boys can use clips for hats, scarves and other accessories.
3) Shoes really need a place to go. Otherwise, they become a mountain in the bottom of the closet. Kids can easily lose the shoe that they're looking for, slowing you down when you're trying to leave the house. Plus, the ones that they don't wear anymore or have outgrown just get buried. Try to get a shoe organizer that hangs over the door, or makes it easy for kids to use. A shoe cubby inside of your front door might be a better place than your kid's closet for shoes.
4) Activities need a place to go, too. Kids accumulate games, arts and crafts, model kits, and other things with small pieces that you may not necessarily want just laying around the room. This is especially true if you have little ones and are concerned about choking hazards. Having games and activities put away in the closet also helps you to keep the room under control when your child has a friend over. Build or install a small group of shelves in the front corner of your child's closet for these things. You can put them up higher if you need to keep them more out of reach. If your child's closet has a top shelf, you might just want to put another shelf a few inches above it. This will make a perfect slot for board games without using any extra space.