I was thinking about the questions/thoughts in your post. They are the kind of questions which are worth asking and thinking about. The Bible makes it clear, at least I see it that way, that the suffering in this world is not imposed by God, but was the result of human sin entering into the paradise God created and sin negatively contaminates every aspect of creation. Childhood leukemia and countless other diseases which cause suffering are truly awful. Yet, think about it, If God took away all the things which cause suffering in this world it would be heaven. But this is not heaven because it is a world filled with sin, sin which people willingly choose to do while rejecting God and the sin-free, suffering- free qualities of heaven.
I am not saying a child is responsible for their leukemia or anyone is sick due to their own personal sin, necessarily. My point is that sin which exists in this world harms and damages the life God intended.
The bible also makes it clear that god made everything, including sin.
Of course cherry picking is an acceptable way to shift responsibility away from the omniscient god of the bible but i prefer to read it as a book, not just selected verses