So is deregulation the answer?
Well, no. When deregulation gets done, the bills are written mostly by lobbyists. The big corporations identify a few of their pain points and we happily eliminate those regulations, but we never worry about the things that are most burdensome to small businesses or the regulations that prohibit new companies from starting up at all. So deregulation tends to strengthen existing companies and reinforce the corporate oligarchy that already exists.
Basically, for the market to work better we need to increase competition, but Congress will never have any incentive to encourage increased competition. That proposition would pit the lobbying dollars of every existing company in an industry against the interests of companies that haven't been formed yet.
If this was a non-ideological/political position we would be having a civil war over bushes spending during his term.
You argue that financial regulation is important (and it is) but the problem with your statement is that the economy is all-important. I'm not going to argue that it isn't, rather I am merely goung to point out that people have very different ideas about what government is for.
For some there are many social issues that Are important to society as a whole. One could argue that freedom of religion is an unproductive distraction.
One can argue that we shouldn't legislate morality, which many clearly try to do, but we do that in many ways. Theft, murder, etc are all morality when it comes down to it.
If you approach democracy by saying "these people are irrational because issue X doesn't matter to the economy" you're not making any useful observation. In fact, it's a bit like arguing that the problem with democracy is that you don't get the outcome you want.
Same thing with legislation. Take an issue like gay marriage. Everyone can understand it at some level, so everyone has an opinion on it and it becomes a popular subject to talk about when discussing politics.
Now take something like financial regulation. The future of the country is riding on it, but it's too complicated for most people and thus people fall asleep after 5 minutes of talking about it, so it's handed off to specialists and consultants who work for the finance industry.