Plucking

Its an age old problem but new to me & I am desperate. My 2yr old African Grey has suddenly started plucking a lot. She is a free flying bird & has a room full of toys & only goes in her cage at night. She also has an outdoor flight cage which she goes into several times a week, weather permitting. I spray her with tepid water three or four times a week, which she loves. She has a wide mix of fresh veg & fruit every day & until recently was eating Harrisons. She is rarely left alone for more than an hour or two & I spend at least a couple of hours playing with her every day.
A few weeks ago I had to leave her with a friend for a week & she was in the same room as her sister. This wasnt her first stay but it was the first time she had seen another parrot.
She seemed fine when we brought her home but she seemed to go off her Harrisons from that time so I ended up buying a well know branded parrot seed & nut mix. A couple of weeks later she suddenly got sick & was sleeping all the time & off all her food. The vet gave her a vitamin supplement & suggested I get her a toy! She was back to normal next day but still refusing Harrisons unless I pulped it to a paste & hand fed it. All seemed fine but.....
Three weeks later I had been out for a few hours & when I got home the floor was thick with feathers. & she continued for the next few days. Another trip to the vet & he sprayed for mites & I have to admit the crazed plucking eased off drastically but she still seems very bothered by her feathers. She does a lot of wing "clicking" (a brief short flap) like she does when settling down for a nap but also seems to shake her head quite a bit. Today I notice blood on her leg where she has been having a go at that.
Her nostrils are clean & I can see no visible sign of mites or skin problems & am at my wits end what to do next.
The only other change in her behavior is that she has got extremely loving recently & wants far more cuddles than ever before. Could it be her hormones upsetting her?
My avian vet is the only one available & he seems unconcerned at this stage & told me not to worry unless it gets extreme. To me plucking till she bleeds is just that so I need more ideas please.

hi Sandra, i'm wondering if she has had a reaction to the change in her food, if she was sick soon after eating the parrot mix. i would personally try her with a different brand of pellet or mix, but please remove the peanuts if they're in shells as these can cause illness in birds.

can i ask you which vet you see as at two years old she shouldn't be having problems like this, unless it is her hormones acting up. has she recently had a bad molt too which could be making things worse? if your grey is still on the seed mix i would advise to use extra vitamins and calcium too. hope all is well x