1. There is a fundamental tradeoff, as you have suggested, between growth and efficiency on the one hand and equity and stability on the other. In a world where some societies choose a high-growth path and others choose the equitable-stable path, the former societies eventually invade or otherwise overtake the others politically and economically. Hence, there is need for a social contract, which you have put under the banner of morality, to shepherd mankind to the safer more equitable path.
2. Morality cannot be legislated, and reliance on social and economic players to exhibit moral conduct voluntarily is a form of Utopianism. There are numerous verses in the Qur'an and numerous Prophetic Ahadith that explicitly characterize mankind as gluttonous wealth seekers. Pious members who are satisfied with little, etc., as you describe, were a minority even immediately following the death of `Umar ibn al-Khattab, as evidenced by the grand fitna and the later paths pursued by the Umayyads, the Abbasids, etc.
4. The mirror-image-problem of this product-oriented regulation of financial markets has been at the core of the current financial crisis. Insurance markets have been generally regulated to keep them from becoming gambling (maysir) tools. For instance, I cannot buy an insurance policy against another person's losses, lest this may be at best a form of gambling and at worst an incentive to harm that other. Credit default swaps and other modern derivatives may equally be seen as forms of insurance, but ones that lack sufficient regulation to prevent gambling. I was tempted in July to buy put options on oil, thinking that a global recession is inevitable and the price of oil will have to fall. I stopped only because I think that this is a type of maysir, because "markets can remain irrational indefinitely, certainly longer than I can remain solvent." Numerous others made the bets, I am sure, and conditional on counterparty risk, some have made small fortunes doing that. The incentive to gamble is simply too great.
There is nothing uniquely Islamic about modesty, contentment, shunning risk and gluttony, or even the prohibitions of riba and maysir. Even those who do not believe in revelation (to Moses, Jesus, or Muhammmad; p) can be convinced that those ancient prohibitions and injunctions were distillations of human wisdom over the millennia. Calling those injunctions and prohibitions "Islamic" strikes many as exclusionary and encourages others to engage in hateful and myopically-triumphalist celebration of our collective failure (Islamic finance is just as guilty as conventional finance for bringing about the current crisis).
It is not clear that majority-Muslim societies are particularly better equipped to solve the collective-action problem required to find a low-growth-low-risk social contract. In a world where others will pursue higher-risk-higher-growth paths, it is not even clear that pursuing that lower-risk-lower-growth path is warranted (isn't that how Madinah lost to Damascus during the time of Mu`awiyah?). Is it possible to reconfigure our rhetoric to make it less exclusionary (avoid separatist and triumphalist use of the "Islamic" brandname) and to convince multiple populations at very different stages of economic development to shun fast growth in favor of greater equity and stability? The dialogue would likely be very similar to the one witnessed in negotiations over polluting rights. Perhaps we can learn more from the successes and failures of this global dialogue than we can from inspecting ancient laws for outdated modes of regulating financial markets.