The problem with some cultures, religions etc. is that they use force to convert, circumcise or otherwise try to get rid of diversity in order to make everyone conform to the same "ideal".
Conversion to any belief system or circumcision or other traditions should be completely voluntary. It should never be forced upon children either. They too should have the freedom of choice. Yes, children should have the freedom to say no to go to church or become circumcised or even celebrate Christmas.
There is no reason why conformity should be forced upon any people.
Diversity is important, we know that scientifically, this is evident in Evolution: Genetic diversity is important because it creates a vast number of features, pros and cons in life and not the strongest but the most adaptable genes in relation to its environment will be selected. This is good, because it means life forms can persist and evolve even during extreme environmental conditions.
If I was God, and if I wanted to create life, I would:
* Create the conditions neccessary for life naturally, so that the life can adapt and evolve over billions of years. Life is too fragile if it is to be created by intelligent design.
* I would make my subjects talk different languages and have differing cultures and opinions so nobody can spread propaganda and conform all people at once.
* I would implement free-choice of good & evil, so nobody can understand what is good and what is evil. Though, I would tell people that evil is conformity against the will of the subjects. Forced conformity is the only thing I would ban.
Thou Shalt Not Conform Thy People!
The Bible actually makes it very clear:
Romans 12:2
Do not conform to the pattern of this world, but be transformed by the renewing of your mind. Then you will be able to test and approve what God's will is--his good, pleasing and perfect will.