What's funny is you don't need all this. You just need to do what Beijing has always done to obtain the effect it wants. Education and propaganda.
The current generation of 25+ people are largely a lost cause as they have already formulated their mind set based on their generation's education and propaganda, which was to have less kids, get better careers, and be more selfish. At best, they can be convinced through incentives to not completely crash the birth rate, but correcting their already formed world views will be difficult, if not impossible.
But the <10 years old population can be influenced through proper education and media propaganda. This will create a demographic gap, but only for about 15 years, because China's demographics problems won't hit until ~15-20 years later, by which time today's <10 years old population will be having children, who in turn will mature in 10-15 years into the work force. China can tank a decade and a half of economic slow down, before the next generation is ready to take up the task.
The main problem facing China today is not "lack of material abundance." As stated before, people in much poorer countries have tons of children. Material abundance isn't really the key to fertility unless your country literally cannot feed itself. The key is the culture of people - especially women - choosing to be "single, free, and fancy." Because they're afraid of pain / hard work, terrified of losing social status, and contemptuous towards family values.
You cannot correct a problem like this via financial incentives alone. No amount of making it easier to have children & buy houses will incentivize people who resent any sort of limit to their freedom to get married or have children. You have to actually change the culture, like what Trump is doing - although in a rather clumsy way because it's not easy for him to take over all the media propaganda in the US, while it is much easier for the Chinese government to do so.
To start, stop all those feminists on Chinese social media telling women to prioritize themselves and not get married or have kids because "all men are terrible."