If a child has bone cancer is that reality or just a problem in our heads?
Saying that pain is subjective isn't the same as saying "It's all in your head, it's not real." It means the experience varies from person to person. Some people (including children) deal with cancer better than others.
If he wanted to teach us a lesson about evil and making the best out of the bad situation then why doesn't he just comes out and speak to us.
The suffering is unnecessary. It is akin to teaching a child not to touch a hot stove by holding its hand to the element yourself, rather then taking the time to simply explain it to the child.
Because many of us simply don't listen.
Rather than a child (who we could argue is too young to understand) a more apt example would be telling adults not to smoke: the effects of smoking have been known for decades, cigarettes are no longer advertised on TV or radio or billboards, smoking is increasingly censored from films, we promote anti-smoking ads and devices, buying cigarettes is getting more and more expensive, and there are fewer and fewer places smoking is allowed. Governments, scientists and doctors all encourage people not to smoke. Unlike overeating (also self-inflicted), smoking isn't necessary for us to live.
And of course every year perfectly intelligent, educated, reasonable adults still die from smoking-related illnesses. They know, and they still don't care. Telling people not to do something does not guarantee that they will listen.
Without God, there would still be hurricanes and
earthquakes. You're right that from a naturalistic viewpoint, this poses no problem. The winds and the rocks obey mechanical laws, and there is no one to blame for the ills we suffer. But if you say there is a benevolent god, then the position is inconsistent. The PoE is not circular. It is pointing out that the set of assumptions that typically go with a benevolent 'omni' god are inconsistent.
That doesn't really seem logical: why would something be be evil in a theistic universe, but not evil in an atheistic universe? Presumably they would have the same effects - whether or not God exists, earthquakes and hurricanes would still kill thousands of people a year. They would also still be part of the natural part of Earth's weather system, and it would probably be devastating if they suddenly stopped.
And those people are wrong, and a great many members of their society suffer greatly as a result. These cultural abuses do not somehow become tolerable simply because these people accept them.
Is there any objective way to prove that? Many things we consider terrible today were commonplace a few centuries ago (and still are in some places today) - and yet their societies didn't suffer. The Aztecs sacrifices thousands and were the ruling tribe before the conquistadors came along. The Romans built arenas to watch people kill each other for fun, and their empire lasted 1,300 years. Slavery probably predates civilization.
While I personally believe in objective good and evil, but this is mostly due to my faith - actually proving it is extremely difficult.