I don't think that using only one design means that God wasn't the creator or whatever you are trying to say. I don't think it means He wasn't creative either.
I mean... for every positive, there will be a negative. Why didn't God make our muscles bigger? We'd be better workers, we'd be more capable of dealing with nature, and so on. We wouldn't be as transportable though. We would need more material to build cars and planes and bikes or whatever. The earth can only supply so much. We would consume more food. Why didn't God make us not require food? In that case, why not air? Why didn't God just create us without a need for anything? Why didn't He make us immortal? We wouldn't love Him for one. He wanted to give us freewill to choose to love Him, He didn't want a Heaven yet.
There is always a negative. Only one set of instructions for all life on earth? God has His ways of doing things. They are higher then ours anyway. Shouldn't worry about it.
And I would suppose you are an evolutionist? Well... that isn't science either. Science is the study of observations. What observations have you made about evolution? I haven't seen any in my backyard.
Peace
I can see evidence of evolution basically everywhere I look. Study genetics or any biology and you see that everything is built from the same molecules. We all originated in stars.
Examine 2 different species of trees in your backyard. Why would anything intelligent and omniscient create even 2 different trees to do the exact same thing. You would think he would have perfected the art and just left one standing. No real reason to keep the other alive and surviving unless it serves a different purpose.
Evolution is evident everywhere you look, you have just been blinded by the bible and the church.
Evolution is science. There is tons of substantiating evidence supporting it.
Life is about survival and procreation. If you die your genes are gone forever. Life is simply a vehicle to transport your genes to the next generation.
God didnt create us. He didnt even mean to make us; we are a product of evolution. No intelligence would make humans. No omniscient creator would knowingly create a form of life that kills everything it comes into contact with. Take a look at your own behavior and then study the behavior of gorillas, chimpanzees, bonobos, or any ape or simian. Our behaviors are very similar.
Humans wage war in the name of god. How godly is that. We use gods name as a facade for the true reasons behind most wars. We use god to take away peoples land. Everything is given to us by god according to some peoples logic. God doesnt care if you live or die. Humanity is so minute compared to the grander scheme of things that its ridiculous to even assume god knows who you are.
Even god himself kills first born children though, at least the god of the bible. Sounds like a rather hypocritical and angry god doesnt it.