The biggest problem with having non-engineers run things is their inability to speak proper English. "Redundancy" to an engineer is a good thing - it means taking precautions against failure. To a non-engineer it generally means "you are about to get fired". Mergers may lead to efficiencies of scale (though mostly they don't) but they also lead to banks which are "too big to fail" because the collapse of any one of them could bring down the financial system.

Nor is a tightly-integrated, fast-moving international network always a good thing - ask any epidemiologist about how (say) AIDS spread around the world.

The BIS is looking at this problem with regard to payment systems. In a paper published this week it warns that there could be problems with the payment and settlement system:

interdependencies have increased the potential for disruptions to spread quickly and widely across multiple systems.
To address the potential for a disruption to spread quickly to many systems, the report suggests that system operators, financial institutions, and service providers take several actions in order to adapt their existing risk management practices to the more complex, integrated environment resulting from tighter interdependencies...

The report's frustratingly light on actual recommendations (especially given its 84 page length!) but with any luck its presence in the BIS bully pulpit will lead to something more concrete soon.

Meanwhile, this analysis (subscriber only, but presented here)
on the effects of capital levels and connectivity on stability. The model predicts thresholds beyond which more connections actually help stability rather than spreading contagion. Of course translating that into real-world policy will be tricky.
Worth a read.