To each their own. I've heard second hand accounts for all kind of scenarios - parents regretting their decisions in their 30s, extremely happy parents, childless extremely happy couples in their 50s, and some with their regrets. That being said, even if you have 1 child to "have some fun with the little person", it's still below 2+ children a couple is supposed to have to fix the birth rate problem.
>>kredd+(OP)
I advise having at least two since they will make each other busy and get out of your hair sometimes. And these arguments are totally decoupled from birth rate problem.