My feelings on the subject have varied a lot. The most beautiful, loving families I have personally known have been large families with many children. I wanted for a long time to have the same sort of family. I was a very quiet, shy, mild-tempered baby and so I'd been counting on getting the same sort of temperaments in my children. But my firstborn isn't like me, beyond having a strong drive to learn new things and an interest in words and systems. He is very intense, social, energetic, and loud in comparison with the rest of my family, and it has been very difficult for me to parent a child of his temperament, even though I love him--so difficult, in fact, that I would be very reluctant ever to have another child. If I had one with a calmer disposition, I could manage it easily. (It is very easy for me to care for other children his age who are of a more reasonable and predictable temperament.) But if the luck of the draw gave me another one like my first, I'd be up a creek without a paddle. I simply wouldn't have the mental/emotional resources to handle this much sensory input x 2.
Then again, if he had someone else to interact with, I may be less drained.
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The machine does not isolate man from the great problems of nature but plunges him more deeply into them. -Antoine de Saint Exupéry