God being omnipotent could achieve any purpose without the suffering. You seem to admit here after defending God against my charges that He is responsible for disease after all.
Just as you asked me to get the nuance of your position, perhaps you could accord me the same: just like any loving parent would, God chose a course of action that means a period of suffering for the long term good of the human family - that is what I believe. I also believe that God is all-knowing and chose the best way for all of us.
I believe that God created us with thinking ability; the ability to create thoughts, to consider them and to choose to act on them or not and this means that he created us with the ability to think and do things that are harmful. I also believe that we are responsible for what we think and do.
So God didn't create thoughts of hatred and violence, humans did. God didn't put those thoughts into action, humans did. God didn't create weapons, humans did. Every aspect of the world of men, including its diseases, was created by men at some point in our history.
John, can't you see that the world you describe is an insanely cruel world? Surely no loving God would allow such a world to be?
So you would have me think: cruelty exists, therefore God does not? The cruel person says: I exist therefore your God does not. And yet God does exist as does the cruel person and so the thinking is in error.
Cause and effect in the world of physics is fine, but in the world of disease the whole point is, it's unnecessary.
Our existence and life is so heavily predicated on cause and effect, it is hard to imagine what you mean by the above. If people set things up so that their drinking water becomes contaminated with human waste, for example, typhoid fever is the result, is that result unnecessary?