Other? I would have thought (I am no economist so I apologize if this is daft) that the sensible response would be to permit all of the banks who engaged in gambling to actually lose their bets and suffer the consequences of their own actions. Those which extended loans which could not be repaid should have entered insolvency, with the debts owed to them eliminated. Likewise, the fraudulent practices conducted should have resulted in hundreds or more of banking executives and other employees sent to prison.
It would seem to me that the solution we settled upon - giving them titanic amounts of money, assisting their consolidation, and playing pretend as if the fraudulent loans issued were still owed by those who they were foisted upon, foreclosing on homes, and significantly derailing, if not destroying, the lives of hundreds of thousands of families - was the 'other economic system' here. It certainly was not the one laid out in black and white on paper and followed for a century or so. Under that one, when you extend credit to someone out of funds you do not have, then place bets on repayment while lying about the odds, you crash rather than luxuriate in the spoils of a looting of the masses.