If God is so great then why is there so much suffering? Again, you'll have to take my word for it that the free will defense is the generally regarded as the best response to this question. You have to pick free will or pain free bliss and free will is better.
Free will is a slippery thing but, even supposing that we have it, not everyone has the same amount of it. And the people who have the most of it could probably stand to have quite a lot more. It's our ability to make choices that suggests we have free will, but because of our biological nature, there are many things that we simply cannot make choices about. Children and the mentally handicapped are less free than ordinary people because we don't trust their ability to take many decisions. Presumeably beings much smarter and more mature than the most able humans are better able to make even more choices and hence are more free.
So, in the future, if we suceed in improving our capacities (becoming more free), and significantly reduce the amount of suffering in the world, what will God's excuse be then?