Have you tried quiet time? We have a rule that DD has to stay in her room for quiet time, she doesn't have to sleep. She gets a break and sometimes she even takes a nap. She's allowed to play in her room or look at books, but she can't come out and get more toys, so her selection is somewhat limited. Of course, I don't want it to be too interesting in there since I'd rather she slept. She doesn't typically play in her room, so it's not like she's playing in there all day and then I require her to spend additional time for quiet time.