A challenge about women and marriage in Islam

[Muslim Scholar]

What would be better than the Islamic law when applied in reality? The western law

Remember that in California they are applying the same rules as Islam
A 9 years old girl can marry a 100 years old man as well.

Now I'll narrow the argument down to just the fundamental things wrong with the islamic law even if everyone did follow it perfectly and not abuse women or children (even though the quran does allow men to beat their wives if they fear their arrogance which I do consider to be abuse)

Judges and doctors get things wrong lots of times why do they get to decide when a girl is mature?

A girl may feel pressured by her parents into getting married and do it just for there sake, at 9 years old it is much much more likely they she will be more impressionable than someone who has reached there teens at least, she may just agree to this under pressure.

let's put some examples
Jennifer which is a 12 years old girl, wanted sex, in USA she will get laid with another boy and may get pregnant, abortion, abused, etc.
The law will not help her at all (except in some states that they will allow her to marry that boy (if she is pregnant), the boy most likely is not responsible nor can support a family)

Under Islam Jennifer will talk with her parents, they will probably make an arranged marriage with somebody they feel suitable for her, even if he is young they (and his parents) will support the marriage till they grew up and decide for themselves.

Men shouldn't be able to beat women based on their assumptions that they suspect their wives are being rebellious or they feel fear of their wives arrogance.

Beating wives happens anyway in many western countries, under Islam it is restricted to be not hard and not on face, it helps a lot in many cases, anyway (as any western country) she has the right of divorce if she doesn't like it too much.

I don't have to come up with an entirely alternative system I just want a system that deducts these things from it, and therefore will not be the Islamic system.

See the example above