If you're into experimenting it may be worth doing so for a week or two to see if there's even further improvement in sleep/breathing; you first have to remove the potential agitant and then let the body recover.

Getting a Neti pot (use distilled or previously boiled water only, along with adding a proper amount of non-iodized salt - Google search will give the answer) and trying that out to help clear the sinuses with warm water seems to help a lot of people as well.