The first thing I need to do in my response here is to make an important distinction that you might not be aware about (because it is made in a different post of mine, the one called Toy Worlds and the Problem of Evil). That distinction is this: if free will is to exist, then even an omnipotent/omniscient God cannot prevent all forms of suffering, such as unrequited love, broken friendship, perhaps boredom while studying, things such as this. God is not culpable for any of these forms of suffering because they are necessary and unpreventable consequences of free will (given the premise that we want to have free will).
However, physical suffering does not have to exist in order to have free will; and an omnipotent/omniscient God could prevent physical suffering from existing. I realize that in a lot of prior posts I have shortened this by saying "suffering," but if you go back to the beginning of this series of posts, I have always meant physical suffering only when I'm saying "suffering." That's also why the chosen example (leukemia) is a physical example.
With that in mind, let me answer your questions. To be clear, these will all be answered under the understanding that an omnipotent/omniscient God could create a world in which physical suffering does not exist, because it is preventable without interfering with free will. Emotional suffering can't be prevented without also preventing free will from existing entirely.
Why wouldn’t preventing future suffering as I described in my last post not be beneficial? Because learning not to touch a hot stove top doesn't help you if the stove top is never going to burn you in the future, it would be useless experience. You never have to suffer in the first place to learn it if it is never going to cause you suffering at all.
Are you suggesting that God should created a world where no suffering would have been possible in which case we would never need to learn any lessons? Yes, as long as we're talking about physical suffering and lessons from physical suffering. Once again, there is no need to burn our fingers to learn not to touch the hot stove if the hot stove can never harm us.
Why would be the purpose of such a life where we never need to learn anything from our mistakes? We would still be capable of making mistakes: if we are jerks, we might lose our friends or loved ones. If we are vain and brash, we might never learn new knowledge since we might assume that we already know everything. In a world without physical suffering, there is still growth; there just aren't things like diseases and deformities and burns and things like this. There aren't innocent victims of violence (because guns would not hurt people, for instance).
We would still have the same kinds of purposes: we can wake up and choose which friends to hang out with that day, which movie to go watch, what new things we want to learn, what poetry to write. The only difference is that we can't needlessly be physically hurt or maimed while going about our business.
Are we going to spend our whole lives just enjoying ourselves? I'm sure there would still be tedium due to the tasks we set out for ourselves. Learning a new subject would still be difficult, navigating social nuances would still be difficult. There would still be roadbumps in life to overcome; just not bodily harm.
If we have a job is God going to be sure we never suffer in our work? God can't save us from boredom (while maintaining free will), but God could certainly save us from having a hand severed off.
If we get married is God going to be sure we have a happy marriage so we never suffer? Even an omnipotent and omniscient being couldn't do this while maintaining free will. So in this case, there's not much God could do: it is up to the humans to prevent suffering. God is not culpable for this kind of suffering.
If we go to college is God going to do all our homework so we won’t have to suffer to earn a degree and we can party hardy? Here's another example where God can't do much. We would still need to learn things we're interested in, and that takes work and dedication for it to pay off. That is not something God is culpable for because it's necessary for free will. Physical injury is not necessary for free will.
If we have children is God going to prevent the pain of childbirth? Yes, this is something God is culpable for (by setting up the laws of physics, chemistry, and biology such that this brings suffering). So yes, this is something that can be prevented without affecting free will.
Just to be clear, are you saying that some suffering is not beneficial, but not prevented by God?
The problem with this would mean God deliberately (remember, because infallible/omnipotent/omniscient) created suffering that is not beneficial: this would not be congruent with omnibenevolence.
If you try to rescue this by saying God gives "recompense" for doing so, that doesn't save omnibenevolence: if I slap someone and then give them something nice, I'm still not omnibenevolent because I slapped them -- even though I did something nice afterwards.
