Get married when you really, really love each other and can't stand being apart. When I fell in love with my intended, it was almost like a physical pain (and I have a relatively high pain threshold). I said to myself, "who needs this?" But, I was already smitten, so it was too late, and we've been happy together for almost 35 years. When either of us has to travel on business, we still hate being apart.
If you don't want kids, do yourselves and the world a favor, don't have them. Babies are extremely demanding, frustrating, and difficult. They separate the boys and girls from the men and women. For the first couple of months they are just GI tracts with sirens on top. How you feel and what you want for yourselves is irrelevant. Your kids come first. They are an incredible responsibility and expense.
And yet, having children can be the most gratifying and wonderful thing you and your partner ever do in life.