Organizationally, I suggest people are motivated by the measurable factors that business plans and compensation are based on. If the business plan metrics are time and cost, managers and even their subordinates are motivated control those. In aviation, "Safety is #1 priority", yes, but safety is not measured (probably not even measurable) and it's not compensated for. So, I would suggest, that in spite of commentary from outside the community, managers are not necessarily cold-hearted, and dismissive of safety. Rather they working to achieve the best results for the metrics in use in their organization. For this reason, I believe, the check-and-balances of manufacturer and regulator is most useful. Different sets of metrics working in tension. The lack of which is likely one reason that the current system has failed.
The current delegation process of the FAA is not the checks-and-balances of the manufacture decision factors that it once was. Oversight is more clerical than technical, now. An engineer raising technical questions and/or objections to a manufacturer's certification plan only create "problems" that the FAA (read "FAA manager") is blamed for and success is reducing or suppressing such problems, at the expense of technically effective oversight. It is difficult for the engineer to even suggest involvement in otherwise delegated compliance findings. It used to be that regulator oversight allowed for an engineer to look into any issue that was delegated. The delegated engineering representatives know this and it helped keep things honest.
Not saying that any system is perfect, but oversight needs to be substantial, not merely clerical. Delegated engineering representatives need to expect anything they do being checked by technically competent regulators, even if a relatively small fraction of their work will be. The difference in the business metrics between manufacturer and regulator is a safety advantage, not a detriment.