Vista is my parent-raised cockatiel (grayface pearl). I have a thread for her but I'm long overdue to post another update. Surprisingly, she is very cuddly, but I would still qualify her as sassy since she's happy to make angry noises if she doesn't like something. If she does 'bite' it's actually much more gentle than my rescue tiel (who is still tame and kind). I don't want to oversell myself - I worked hard but I am sure having another tame cockatiel around for Vista to see me interact with was a massive difference maker. Does your girl see you interact with your other birds regularly? I don't know how flock oriented Alexandrines are, but from what I've read, it sounds like they aren't too solitary?
I'll be honest, I don't trim my tiel's nails unless the are at the vet and look overgrown. I just wear long sleeves.

Vista won't let me touch her feet. Candela (rescue tiel) will, but the second I try to hold one of her toes she protests. I'm also a bit nervous of them jerking their foot and getting a toe cut! It sounds like you can trim your other bird's nails and that you might have some big ones. That's very impressive you were able to train them.