We don’t get any discussion of how creditors react. We know that creditors can benefit from the current bankruptcy laws, but there’s nothing that indicates creditors' reactions to these laws — are they surprised, pleased, supportive, etc. We just don’t know.

“Chief” is too strong. Although we know they do benefit, we don’t know that creditors are the main beneficiaries of bankruptcy laws.

In the line that uses “perhaps unexpectedly,” the author discusses the effects of current bankruptcy laws — they’re helpful to debtors and to creditors. But the line doesn’t involve what went into the “formulation” of bankruptcy laws, which involves how they were written. What’s unexpected has nothing to do with the writing or making of bankruptcy laws, but rather, with the effect of bankruptcy laws.

The line in which the highlighted phrase appears expresses the idea that bankruptcy laws benefit debtors and creditors. The benefit to debtors is expected; but the benefit to creditors is not, on its face, something we’d expect to happen. But creditors actually do benefit when debtors are helped, because creditors have a higher chance of getting more money back.

In the line that uses “perhaps unexpectedly,” the author discusses the effects of current bankruptcy laws — they’re helpful to debtors and to creditors. But the line doesn’t involve what went into the “formulation” of bankruptcy laws, which involves how they were written. What’s unexpected has nothing to do with the writing or making of bankruptcy laws, but rather, with the effect of bankruptcy laws.