I'm saying it's not inevitable at all, without a blueprint.
As above, utilizing randomization and selecting for fitness function is a very elegant way to arrive at a design goal. I've used the same to determined the most efficient way to drive a car with specific parameters around specific courses, try a vast number of random teaks and keep selecting the fastest time. The interesting thing is that to reproduce the results, the most efficient way is the same as finding it in the first place- simply run the particular seeding of random numbers that produced the desired result. An alien investigating the code would see nothing but the appearance of random changes producing very 'un random' looking results. The result was both the result of random changes and very specific design at the same time.
Those are very poor analogies. Do you actually crash your car, killing yourself each time you test a driving method?
Do your other experiments have a significant chance of giving you cancer? Cancer is, after all, entirely a product of the exact same mechanism by which evolution occurs, and it shows its vast capacity for error. Cancer is also a billion times more common than adaptive mutation.
The real problem here, though, isn't the numbers, the question-begging (though that is a problem), or even the taking of Occam's Razor out back and shooting it. The real problem is that the designer you're imagining is a freakin' psychopath, literally killing and maiming sentient creatures left and right in order to arrive at... something or other that we can't possibly fathom. Creationism is one of those things that people
think they want to believe because it would ostensibly give them comfort, but if you actually examine it in any detail the result is precisely the opposite.
So, no evidence whatsoever of a blueprint, plus an utterly untestable hypothesis that there
is a blueprint, which only leads to some very squicky places. Not seeing the appeal here. I guess some folks just need to feel that there's somebody in charge, even if it means being ruled by a Dark Lord of the Sith. Fortunately, there's no intellectually honest reason to adopt the blueprint hypothesis, so we don't have to investigate questions such as why God thought giving my grandfather colon cancer was acceptable collateral damage for his grand plan of... playing in the sandbox.