As much as folks here might not want to hear it, throwing an army of mediocre (or, ideally, decent) developers at a problem and paying through the nose for managed infrastructure often winds up being a much (much!) cheaper way to arrive at a good outcome than a smaller number of more skilled engineers with a shoestring infrastructure budget.
Have you ever worked with mediocre developers? Have you ever been responsible for a built-out implementation of the sort you are talking about?
And, have you ever actually run intensive tasks on hardware where you owned the entirety of the system and could have visibility into the full OS? (Many VM providers oversubscribe their CPU and RAM, and, you have no visibility into memory bandwidth performance either.)