I had tried everything (except that stretch with the stairs which I will be adding today!) to get relief and my PF didn't ease up until I started putting ginger root in my daily juice. I would assume you could get the same results with capsules of the stuff, or off a spoon if your made of stronger stuff than I am.
I just took a job working on my feet after 18 years of riding a desk, and I flared back up. Added some insoles and Advil to the ginger for a week and now I'm back to being able to go barefoot with my flat-footed self. YMMV