I was in the temple recently watching the creation narrative and it struck me how much the creation tells us about the atonement of Christ.
The great power God has to create worlds tell us about His power to create great changes. We need to change when we repent and the greater the change we need, the more we need that assurance that Christ has that power.
His ability to bring plants and animals tells us about His ability to help us grow. We need that for faith in His power (grace) to help us reach greater levels of righteousness than we've ever had before.
The long period of time it took to create the world tells us about His great patience. If He could wait for the earth to obey His commands, He is going to be patient with us as we grow. He can't be discouraged. (But just because He could wait for the earth doesn't mean that we have all the time in the world to do our part. We only have so much time in mortality to do our changing and improving in, so the sooner we get cracking, the better for us.)
The way God pronounced it all good when it was done gives us hope that when we have finished progressing, He will similarly pronounce us good as well. It tells us God's approval can be attained. (What a wonderful thing that will be!)