Testimony

I was raised as a Muslim and practiced Islam with my own free will till the age of about 23. At that point i started to read the Quran. I was always told that Quran is the direct and unchanged word of a loving, caring, passionate god, and the Quran's message is eternal, and for all people and all races.

Reading the Quran carefully brought doubt to my mind, raising questions like:
1) why is Allah so obsessed about Muhammad's sex life? (sura altahrim aya 1)
2) why would Allah tell another man to divorce his wife so Mohammad can marry her? (sura 33, aya 37)
3) why would allah put a seal on a person's heart, make him blind and deaf to the 'truth' and then punish him in hell? (sura 2 aya 6 and 7)
4) why should a woman be beaten? (sura 4 aya 34)
5) if we r meant to fast between sun rise and sun set as quran says, what happens if we live on the north pole where in the summer the sun does not set for 6 months? Is Islam not for the north pole?
6) why should Mohammad's widows not get remarried? I was told the only reason Mohammad married so many women was because at the time that was the only way to support a widow. In that case, what about Mohammad's widows?

After this a very important question came to me... Is there anything that can be described as GOOD that can be accredited to Islam?
And to this day, i can not find one good thing that has come from Islam, nor can i find a Muslim who can name one good thing that comes from Islam. If anyone out there can, let me know.
Thank you

Arash