Realsome: In real life just beliving ain't enough, you are asked to go to a moske talk with Iman and show him you really belive in Islam, if i don't do it i ain't considered legally a muslim ;)

Rayyz: I would say that a true perfect being as God is supposed to have only 1 message to all his creations and no favourites, so, every contradiction amongst the 3 main religions should be corrected to the one that is similar to majority of the 3 religions.
You are right, Hell/Heave are man's creations to make people behave and fear the afterlife.
The best example of Humankind assuming God's wishes are the clericals that say that only their religion is the correct one and all others are wrong, that's 2 reasons why i'm a monotheist like Abraham, Moses, Jesus or Mohamed, every christan/jew/muslim is considered a monotheist that were taken away from Monotheism by some supposed God's prophets that instead of uniting God's children, splitted them in, supposably, diferent faiths, all that God wants from us is to do to others what we would like them to do to us.

Only God Can Judge Me
الله فقط يمكنه محاكمتي

I am you and you are me, if you love i love, if you suffer i suffer
أنا أنت, و أنت أنا, إذا أحببت نفسك أحببت نفسي, إذا عانيتَ عانيتُ