Onboarding & KYB Friction: Experiences with Different Brokers

Curious to hear about other folks' recent experiences with onboarding new brokerage accounts, particularly on the KYB side for prop firms or even just larger capital allocations with retail brokers. I've found a surprising variance in what seems like standard practice for identity verification and proof of funds. Some processes are seamless, a few clicks and you're good; others feel like pulling teeth, with repeated requests for documents that were already provided, or extremely slow review times. It's frustrating when you're ready to get capital deployed, but stuck in bureaucratic limbo. Has anyone found a consistent correlation between a broker's or prop firm's size/reputation and their KYB efficiency, or is it more of a roll of the dice?