Just reading through and two things:
The merging between investment banks and commercial banks is most likely what saved most banks during the crisis. Allowing banks to merge means you are able to hedge your investments from things like a housing/market crash. If you've backed your 401k in only USD, you would have been whipped out, as an investment bank would have also be able to back your savings in other securities, commodities, currencies, even Gold. Without being able to diversify, many investors would have lost alot more. So no, Glass Steagall really has nothing to do with why banks take on risky investments.
By eliminating “off balance sheet” accounting, I'm assuming you mean Shadow Banking. That's already very much illegal and was illegal even before the crisis, however the FED typically allows this by allowing banks to pool resources at the Federal Reserve and paying the banks interests on their pooling. This is done even to this day and the Government allows this.
I'm going to keep reading more.