You are not being unreasonable to have asked, but you are unreasonable to argue once you received your answer.

Neither seat guarantees specific dimensions. The fact that the first one was not to your liking does not entitle you to move or to a refund. You chose to move to the second seat knowing that you might have to pay somewhere between EUR 0 and EUR 85 for it. In fact, the FA told you that she could not commit.

At that point, your options were three: 1. Stay where you were. 2. Move and accept, as you did, the risk that you might have to pay EUR 85. 3. Ask the FA to consult and obtain an answer for you and remain in place until she did. It was your choice. I would not expect AB to waiver no matter how much back and forth occurs.

As to the delayed luggage, AB is stingy. Most carriers would either reimburse reasonable expenses upon presentation of receipts or have provided a flat allowance such as EUR 25 in the form of a prepaid card. But, to be frank, given generous carry-on allowances, one would presume that you've got enough to get you through a few days. Rather than fighting all of this, why not simply make a claim on your travel insurance and let the insurance slug it out with AB?