Good post.
Welcome to the club!
It's also nice to have someone actually working in the field add their comments to the "discussion".
But likewise it doesn't mean that all except for this one mutuation that resulted in us WON'T mutate either.
Some of the population will stay the same, and provided that niche still remains, the original species will as well. The intermediate steps along the chain from apes to humans either interbred or were outcompeted by modern humans. There are arguments for each case.
But wouldn't there still be some members of the ape species that would continue to evolve? Just because these others were "outcompeted" doesn't mean that the tendencies toward mutation and evolution are suddenly "afraid" to come out from that point on -- unless somehow both apes and humans developed genes that miraculously bred these tendencies to mutate out of both species. In other words, given the great lengths of time we're talking about, it follows that there was plenty of time for other mutations and species to evolve after these groups were "outcompeted" by the modern human, would they not?
Also, I am a Christian and I believe that God created life and mapped out the whole thing.
I do too, and it's quite possible that "evolution" is the means God chose for creation. With minor differences, the story in Genesis very closely parallels the sequence of the appearance of the various life forms that is conventional wisdom among biologists. I don't subscribe to the earth being 6,000 years old. After all, God, being the inventor of time itself, is by definition no slave to time and is therefore not in any kind of "hurry".
I do believe there was a Garden of Eden and that it really was perfect, and I hypothesize that the effect of Original Sin was retroactive in time, turning the original peaceful creatures into violent carnivores with flesh-tearing teeth, etc.