The church tax is not mandatory. You simply tell the tax man you don't want to pay it. But it's easy to see how newcomers can be caught out by the rule there. Germans usually only declare a religious affiliation on these forms if they want to be known as members of that religion and pay the tax. Also, the East is far less religious than the West.
Women's rights are a mixed bag in Germany - backwards in abortion, advanced on childcare legislation or other parenting aspects such as working mothers caring for a sick child.
There is, for instance, the legal right for every child to attend a creche or kindergarten run by your local authority from one year of age. If you can show the council was negligent in not providing you with a place for your child, you can sue your council. And if that means you lose income because you cannot work, the council will have to pay you either your loss in earnings or reimburse you for the fees you pay to a private childcare provider. Challenging your council in court over this is free, and women, many women, have successfully done so.
This has been an effective law in that it has forced local authorities to create more childcare facilities, which in turn improves the opportunities for women, especially in the West.
East German women did lose rights with the reunification, something that is barely acknowledged today. But even though the rights of all German women in law are now the same, the historically better women's rights situation in the former GDR still has an impact on their rights across Germany being different in practice today.
When it comes to the childcare I mentioned above, for instance, East German women have an advantage, as they all had free childcare from 6 weeks after birth and that level of coverage has largely remained. A fulltime place (50 hrs per week) is often free and if not usually costs parents no more than 50 Euros per week, a fee that is mainly intended to cover the costs of food or nappies.
In some areas in West Germany, mothers can struggle to find any place at all, let alone a fulltime or affordable one.
Or if you want to access an abortion in East Germany, provided you meet the legal criteria*, finding a medical professional to do it is unproblematic. In West Germany, depending on where you live, it can be a nightmare or even impossible.
(Some I agree with or can accept, others are onerous or counterproductive. The latter are in my view informed by prejudice about women rooted in patriarchal beliefs.)