a main goal of Bill Clinton was to create affordable housing for the lower class.
Was it? Or was it to allow people to become homeowners whether they could afford it or not? And how was this injustice (the giving of something unearned) supposed to be in the public good? And wasn't one of the main methods used to achieve this goal the forcing of lending institutions to give out mortgages to people who would normally not qualify for them? And wasn't a high rate of defaults and the eventual crisis that it precipitated predictable enough that the goal was probably ideological rather than pragmatic, i.e. one that didn't really considered what the public good is at all?
Your problem here seems to be that you want to reduce a very complex phenomenon to a single cause -- "it was greed in the kitchen with the knife," or "it was government in the living room with the candlestick." Any such analysis is likely to provoke the sorts of criticisms you have been getting so far. You need to acknowledge the complexity of the situation, and look at how every party involved managed to screw up in some way.
The government, under both Democrats and Republican leadership, pressured banks in making bad loans. Democrats believed that banks not lending to bad credit risks was discriminatory (because minorities were disproportionately affected). Republicans believed that increasing rates of home-ownership would validate the notion of America as a land of opportunity, while allowing the party to shed it cold-hearted image.
The banks, having been forced into folly, compounded the situation by slapping ridiculously high interest rates on the mortgages, essentially squeezing poor people for money they didn't have and making sure that the defaults the rates were supposed to compensate for would in fact happen.
Said poor people didn't let that stop them from taking on the mortgages, though.
And Wall Street got in on the deal by playing financial games that let the mortgages in question be transferred en masse from one institution to another. People were eager to acquire them, because the rate of return was so high thanks to the high interest rates. The risk wasn't recognized, or was overlooked, or was expected to only kick in after someone else had acquired the package.
The tendency now is for people to place most of the blame wherever doing so is most ideologically comfortable. So, if you're a big fan of capitalism, it was the government's fault for interfering in the free markets. If you're a socialist, it was the banks fault for trying to rip off the poor. And so on.
Perhaps you have put the cart before the horse. Mayhap you should do your research first, then come up with a thesis, rather than coming up with a thesis and picking sources that support it.