Oh, guys! Thank you so much for the words of encouragement! I am coming with another (possibly last) update.
Ingrid is doing better (or so we think). Right now she is on my back under a hoodie (she's feisty and won't sit with me otherwise lol). As you can conclude she does (kind of) let me handle her, be it calmly only for a few seconds and then with some struggle.
I have also learned to handle her better and she now even knows how to let me know when to back off (I can't see well, which makes visual cues difficult, so we had to find a way for us to communicate that with light nibbles. 2 nibbles means to get away from me, 1- I am no thrilled, but keep going). The way I handle here now is with both hands keeping her legs in one hand so she can't scratch because those are talons and not claws, and with the other holding her hands a bit closer to her. Ingrid did not try to bite yet, so feels like we are doing good. Then again, when I took her out of the hoodie when she almost ripped my armpit apart an hour ago we enjoyed some squeals and a couple of quiet hisses (she does that even to other rats, so I am not fussed too much), but I think right now she is having a wee nap on my back. She is proving herself to be a very sweet and gentle rat, so here's hoping that we'll manage to get a bit closer over time. Maybe our scary rat Lila can help her with that too as Ingrid is approximately as timid now as Lila once was.
She played with us on the couch for a couple and sadly, unlike everyone else, she likes the floor, so when she went from under the blanket, she purposefully (but without much panic) went on the floor and just went off running on her marry way. We had to catch her of course and she almost climbed up the cage over the section of our other couple. To be honest, terrified both of us as we thought they'd attack, but all is good, they were more interested in me Not the best experience for everyone, so we decided to work on rat-proofing the whole lounge in the future so that the girls will have a hell of a playground.
We are starting with intros tomorrow, with the same agenda as planned, so wish us luck, and I hope Ingrid doesn't make it more difficult then it needs to be. But hey, she now takes treats, lets you pick her up (kind of) and you don't need to wear gloves while doing any of it. I'll take it as a win!