Before you decide whether or not it is good or bad to want a big family, ask yourself a few other questions first. Is it bad to bring more children into the world when there are already so many that need loving homes? Can our environment handle more humans? How many children can I actually afford to raise, on my own, without help from government agencies? Can I provide quality time for all of those children, separate or together? How will I provide for many children if my spouse dies?
Raising kids these days is no joke and by no means easy. I have one daughter and often find it to already be a struggle at times. It costs a lot of money to bring up kids. From the time they are born you will work your self half to death providing food, shelter, clothes, and the millions of other numerous things that go along with raising kids.
I do not feel as if it is a bad thing to want a big family. I do however, think that it's a bad thing to be irresponsible in planning a large family without the means to do so. Is it fair to all of your children if you can really only afford to raise one or two of them within your capabilities? As humans, we need to understand that we are in crisis. Energy needs are at an all-time high. Drought plagues the planet in areas, reducing the amount of food being produced. How is it even possible to have a big family in good conscience?
I don't think that humans understand fully the effects that overpopulation is having on the planet. In a more simple time, large families were more appropriate. Now is a different era. We must look at breeding in a more logical way. At the current rate of 20 births per 1000 people, how can we possibly provide for ourselves? Money can buy many things- but what if there was nothing to buy? Is it in our best interest to put ourselves in a position to face possible starvation? Not if you ask me.
In the end, it comes down to personal choice anyway. Here in America at least. I must say that I am unimpressed by our inability to identify this very real issue. Don't have more than 3 children. Adopt one or more if it's that important to you.
So, is it bad to want a large family? No, it isn't bad. Being irresponsible is bad. Over population is bad. Starvation is bad.