We have somewhat the same problem with our 5 y.o. dd--she also grinds her teeth, which may or may not be a related thing.
If your dd is not showing signs of a cold, but still seems stuffy, it might be due to seasonal allergies. We have all been hit very, very hard by them in our house. Don't know how you feel about over the counter decongestants, but when taken in moderation, they do seem to make our kids more comfortable. I am not familiar with homeopathic remedies for allergies, but I'm sure someone else here can fill you/us in.
Also, put a humidifier in her room--that really seems to help. I need to go out and get a new filter for ours.
I wouldn't necessarily jump to the idea of surgery--but do bring the condition up to the ped., and, if they recommend it, go to a good Ear, Nose, Throat specialist. The ENT would ultimately be the one to oversee treatment for any of those conditions--sleep apnea, etc., and to do the surgery, if you were going to go that route, so you would want to establish a relationship early. The first time I went to see our ENT, I figured him for a real surgeon, all "cut, cut, cut," and to my surprise, he took an extremely conservative route, and still feels it is not advised to remove our dd's tonsils and/or adenoids.
Let me know if you want to talk more.