Onboarding headaches for scaling up a prop firm

We're trying to scale our prop trading operation, expanding beyond our initial tier of traders. The biggest bottleneck right now isn't talent acquisition, but rather the sheer pain of getting through the KYB process with various brokers and prime-of-primes for our new cohorts. Every provider seems to have their own unique flavour of 'rigour' that often translates to glacial turnaround times and seemingly arbitrary requests for documentation that even our lawyers scratch their heads at. It's a real drain on resources, both human and financial.

Anyone else experiencing this kind of drag? Any silver bullets for streamlining this without compromising compliance? We're talking about onboarding dozens, not just a handful, and it feels like we're reinventing the wheel with each new relationship.