Let's not forget that if a genetic trait is not expressed, or that it doesn't somehow aid in reproductive success, it is useless evolutionarily speaking. This means that if there is a small change, it better have a significant superior trait in order for it to become commonplace. I would call that a big change.
These changes must come in clumps. What good is the larger brain size unless you also get the larger skull, interconnecting nerves, increased blood flow, etc, that come with it? I would call that one amazing ludicrous step. There must have been a point at which an animal that we call ape gave birth to an animal that we call man (primitive or whatever). Even more incredibly, this man had to mate and his offspring had to carry and express his genetic traits.
Evolution is filled with these ludicrous steps. Consider, for example, the evolution of an eye. You have to have an eyeless animal give birth to an animal with a functional eye(s) to make any evolutionary sense. -The supporting skeletal structure and muscles, the lens, the retina, the optic nerve, the connection to the brain, etc. - the list is endless. Miss one of those parts and you just have an ugly blob on the face of an organism that no other organism is going to want to reproduce with. (I know, I know, they can't see it - but you get the point). When you consider the incalculable odds (easily statistically impossible), I'd say we've got a miracle.
Nick, I'd love to hear your several plausible theories of how life started. Aliens? So far I've seen evolution and something involving a higher power. I believe most choose evolution for the simple reason that they don't want to acknowledge a higher power. But isn't evolution just too incredible left alone? At least give me that you see my point.