The answer is that good and evil are just human perspectives. His plan is beyond our understanding and is neither good nor evil.
If anything can happen inside this incomprehensible plan, what is different from there being no plan? If you don't believe anything concrete about the plan, if there is nothing that is impossible because it would be against the plan, then isn't everything just as it would be if there was no plan and no god?
One issue is that it lets go of benevolence. Which works but raises the question of why we'd want to worship such an entity, and what does morality even mean anymore if it's supposedly based on an entity whose reasoning is inscrutable.
There's also that power removes excuses. Eg, Christof resorts to methods like "killing" Truman's father because it's all he can do to maintain the illusion. But if Christof had a whole planet to work with that'd instantly stop being a morally grey thing and just be plain evil. An actual god effectively has no excuses, because there are no limits forcing any kind of compromise.
There are many episodes in my life that were horribly difficult while I was going through them, but later on, I see how they have changed the course of my life and have benefited me deeply, in a way I couldn't foresee while going through the struggle.
The "problem of evil" also assumes that a world filled with automatons with no choice to do anything except submit to God's will is somehow superior to a world where anyone can choose to follow the Way of Life while surrounded by those who either haven't chosen yet, or have made the choice not to walk that path.
Eg, sawing somebody's leg off without anesthesia was the best we had before anesthetics. Today it'd be outright barbaric outside of extenuating circumstances like anesthetics being unavailable in some sort of emergency.
Whenever we get to the point where we can fully and painlessly fix up somebody's leg by using some sort of scifi device, then cutting it off even with modern anesthetics will become morally unacceptable as well.
The more ability, the less justifiable suffering becomes.
Your statement "Suffering is anathema..." is Enlightenment thinking that has had a devastating effect on the physical and mental health of the cultures that have adopted it.
Resilience is only necessary if there's some purpose to it.
> Soldiers are trained into this mindset and can accomplish much more as a result. Athletes train this way as well.
Right, as a means to an end, for lack of a better solution. If we could accomplish those goals without suffering, we would. Suffering is a last resort, not good in itself. It's a compromise. An all-powerful entity doesn't need any, thus loses any justification to resort to it.
For example, if everything was known and easy, wouldn't we be completely bored? Is boredom not also suffering?
For instance, transhumanism. No, we don't need to create a religion, but set a good chunk of facts and laws to govern ourselves. The American and French revolutions were a good step on that against the Old Regime around the mentioned Neolithic.
Certainly a god could come up with a plan that didn't require multiple instances of genocide and children dying of incurable diseases.