SJSinNYC I have been following some discussions here without posting and I totally agree with you about tuition. BUT do not think that by deciding to have less children it will improve your financial situation. A person is judged on Rosh Hashana how rich or poor he will be that year irrelevant of how many children he has.
Someone came to the Steipler Zt”l and said that he does not want anymore children, he has enough problems with the three kids he has. The Steipler answered him that a person gets a certain amount of tzoros in his lifetime so either you will have your alot tzoros from three kids or your tzoros can be spread out amongst five six or seven kids hence each problem is smaller and less painful since there are more of them. But a HKB”H does not decide how many tzoros a person will have by the number of children he has.
Remember the words of Chazal “Bo tinoik le’oilam vekitzva beyadoi.