One woman and no male testimony suffices if the evidence is for a matter where a woman is an expert, for example a midwifes testimony is sufficient.
Brother's get twice the inheritance their sisters get if the parents die intestate. The brothers are financially responsible for their sisters, including those who are divorced an return home. Womens finances are their own, they are not required to financially support anyone.
A woman can indeed marry herself, I have done. A young woman chooses her male family members to act as her guardians and they put forward her marriage contract and conditions she wants in her marriage contract. Older women, divorced, widowed women can do it themselves as they wont be shy about and less likely to waive their rights.
Divorce in Islam is allowed, a husband can divorce his wife by saying he divorces her, in cases of divorce there is a three month cooling off period wherein the couple can reconcile, this is only allowed three times. A woman can ask for divorce, she doesn't need a reason, that she does not wish to be married is sufficient. I got a divorce it was a damn sight easier to get an Islamic divorce than a legal one.
Where both parents are equally able to care for their and neither is abusive custody of a child under the age of seven goes to the mother, after the age of seven the child's wishes are considered and the father gets custody if the child wants to live with the father and there is no abuse and the father is equally able to care for the child as the mother.
The father is always completely and utterly financially responsible for his children he must cover full financial responsibility of his child and the mother (being his ex-wife) and his child for the first two years of the child's life if the mother chooses to breast feed their child.
Custody means the child sleeps at his fathers house not that the mother is prevented from seeing the child. It's meant to safeguard the child from abuse and make it easier for the mother to re-marry, it also ensures the father does shoulder full financial responsibility for his child. I have full custody of my children and nobody is suggesting I hand my DC to ex who was abusive despite being re-married. I have a friend who has full custody of her two DC awarded her in courts in Pakistan.