Moreover, it seems to be very likely that God actually intends to put evil in the world as an intermediary to strengthen people’s faith and ultimately align with goodness — Isabel Hu

I agree with your objection to premise 1c. It’s not that God cannot eliminate evil, but more like it is a necessary evil in his ultimate plan. This sounds like the Soul-Making Theodicy, in which God allows evil and suffering in order to develop humans into virtuous creatures capable of following his will; trials to make souls holy. This can be supported by the Temptation of Christ (Luke 4:1-13). Satan tries to tempt Jesus as he walks through the wilderness. Jesus successfully resists temptation and that further developed him as the perfect lamb. As the Bible says, the perfect lamb was born to die on the cross for all of humanity’s sins. Jesus had to go through many trials to show that he was tempted as we are and then how he was able to overcome those trials. Those trials strengthened and elevated Jesus’ soul.

he somehow intentionally puts evil in the world and considers it as a method to strengthen people’s faith and guide them to ultimate goodness — Isabel Hu

In this sense, I believe the Problem of Evil exists, just not in the way you’d think. The Problem of Evil argument implies that it’s God’s problem with evil. And since evil exists, that must mean God can’t solve the problem. The Problem of Evil that I propose is that it is mankind’s problem with evil. Evil is the problem that mankind must solve. God purposely places evil in our way so that we must come up with a way to overcome it. Evil is a piece in God’s plan.

A response to this Soul-Making Theodicy is that some people die before they are made holy by God’s trials. To that I say, free will. People are free to do as they please because of free will and that is why some people fail to make their soul holy. And people who fail soul-making, their failures can affect other people’s lives. Others’ free will becomes an obstacle that some people cannot overcome.