Terry - Thanks for posting about that aloe juice. As Victoria mentioned, we order a bottle for avian use from the bird store, so guessing we pay way more then needed!! And having it readily available, we would use it much more freely.
For the dry itchy skin, are you bathing on a regular basis too? Also, just taking Sophie into the bathroom with you when you shower. We have one of the shower perches and even on days when Ivory does not get a bath, I put her on bathroom mirror just so she gets a steam bath

She sounds like she may have been doing something similar to Sophie, not actually plucking, but she would overpreen under her wings, she would lose the little tuft down feathers or you could feel they were kinda in little knots. Now after regular bathing, steam showers, aloe spray and also finding toys that she really likes, she is finishing up a molt and under her wings are so soft and smooth now! We went to the vet today and she was so happy to see the turnaround.
There are also some herbs and teas you can try that are reported to help with plucking issues. We've been doing quite a bit of reading with Victoria's incoming rescue adoptee Folger, who is a major plucker. Red clover is reported to be very helpful for pluckers. I picked up organic chamomile at Wegman's to make up a tea for Ivory when she gets stressed or upset. Gave her a few blossoms today to chew on before going to the vet. Think it was not soon enough to help with the visit, but on the drive home, she slept like a rock most of the way! We don't have hands on experience yet with the red clover, but wanted to share what we've been reading, Folger won't be home for a couple weeks probably, I will let you know how it goes when we try it if you are interested!