One thing that struck me over and over again while watching these shows is just how bizarrely improbable life seems to be in so many aspects. Even knowing that every single adaptation is ultimately explainable by the basic principles of evolution, time and again I find myself asking how such a thing could have possibly happened "by chance." Yes, I know that chance just explains the process of random mutations and that everything else is "driven" by the process of natural selection, but the extreme variety of life on this planet and the extremely specialized adaptations do make me understand why a lot of people believe that there must somehow be an intelligence of some sort driving the whole thing.

I'm not sure you have fully grasped the concepts. Once you have life -- organisms that replicate with random variation -- the ever increasing complexity and adaptation we see are not bizarrely improbably at all, they are more or less inevitable -- although there is randomness in the exact shape that adaptations end up taking that things do adapt and get more complex is not "bizarrely improbable" at all. Have you read Dawkins book The Blind Watchmaker? He goes into this in great detail and gives some examples that help clarify the concept such as a simple computer program he wrote that has guided replication and comes up with complex "designs" without a designer.

As for the question about creationists and the cruelty of nature in my experience theists answer it in a number of ways:

1) When we are talking about cruelty inflicted by humans that is "the problem of evil" God gave us free will and humans choose to do bad things.

2) When it comes to the cruelty in nature such as the wasp example they do tend to gloss over it in my experience. The most common answers I've heard is that animals don't have souls so they don't really suffer or their suffering doesn't matter. That and that nature (which they see humans as not really being a part of) was put here by God for humans so again the suffering of non-human animals doesn't matter.