Onboarding Friction for EU-based HFT Desk - KYC/AML Realities

Running a mid-frequency statistical arbitrage shop out of Brussels, we've hit a wall with KYC/AML onboarding across several tier-1 liquidity providers. The documentation requests for beneficial ownership and source of funds for multiple legal entities within our structure, while understandable in principle, seem to get bogged down in internal compliance departments for months. We're well-capitalized, regulated, and have a clear paper trail, yet the process feels like trying to push a boulder uphill. Is anyone else experiencing significant delays – specifically with European LPs or prime brokers – when trying to get an HFT desk integrated? Or are there specific pitfalls we should be avoiding to streamline the process for our next integration, perhaps around how we're presenting our corporate structure or pre-empting specific document requests? It's burning resources just waiting for account approvals.