Millions of designer babies - Would society aim for uniformity or diversity once we have the means to fiddle with the human genome?

Suppose biotechnology develops the capability and a future society finds it acceptable to design the genome of our babies (using the fertilized eggs of parents as a basis).

Would practically all babies have an IQ of 150 or more? Be strong and athletic with an ideal weight? Have talents for almost everything valued by our society? Be good-natured and have a natural tendency to be happy? Be free of illness?

Or would some parents choose less intelligent babies because society wouldn’t work otherwise? Focus on one or very few talents only to make it easier for their children to choose a profession later in life?

So will we see more uniformity? Or will we be able to keep our diversity? What would large-scale genetic engineering really entail?