In Eighteenth century, rich men were judged by the size of their family. But recently, the size of family has little or no effect on financial status of one. Both type of families has its own merit and demerit.
Considering the economic and financial situation of today, we would say a small family helps in proper planning as well as budgeting. Also, utmost care and attention can be given to the children. For example a family of four, the children will be provided with the best level of education that can be affordable by the parent, expenses on the children will be minimal compared to that of a larger family, the children can also have access to their parent without being scared of what the others may feel.
However, the negative part to having a small family is that the kids mostly tend to live the dream of their parent. As such, emotional blackmail from the parent do set in and these affect the child a lot. Another factor is the phycological effect these types of family could have on the child. Most of these kids turn out to be an introvert, they enjoy their space and find it rather too hard to adjust when they are outside their comfort zone.
In conclusion, in as much as economic and financial factors are our major concern, the children well-being should be our utmost concern.