I would say it's definitely worth it to revisit Advair and adding it back into your routine. I was never a fan of the diskus, but I really like the Advair HFA. Definitely use a spacer with it, to avoid thrush, and always rinse your mouth out with water (spit! not swallow) to further avoid thrush.
JenWren, have you tried the Advair HFA with a spacer? I always felt a "film" on the back of my tongue with the diskus, but I don't notice it at all with the HFA and spacer combo.