It seems to me the problem of evil is a real problem, and it is my main barrier to faith. I just have trouble believing in a benevolent creator that cares about people- I see no evidence for it in this world. There is gross unfairness and suffering in the world and I don't believe Christians can account for it.
I grant that I could be wrong, that somehow there is a God in charge of it all and its just like the Christian God and is beyond my understanding. But it would be pretty cruel for such a being to hold honest doubts against me, given the quality of evidence he's left.
And honestly, if it is the case that God exists and he has such a mysterious plan, what does that say about Christian epistemology? How could we take any religious authority seriously if God's will is so inscrutable? It seems to me much more skepticism of religious claims are warranted, regardless of whether or not the Christian God exists.