Also everything you said here is extremely generic, it doesn't address the initial problem of finding a problem that a company needs solved and will pay for, but wouldn't solve themselves internally.
I'm working with a client right now at a 30h/wk retainer. I solve problems for them and communicate with the team regularly as if I were an employee. In my experience it's easier to sell your value to the C-suite because they focus more on outcomes than line items or specific tasks. Relationships, reputation and positioning are key.
Duh. If a general way to find such problems existed, everybody would be using it - meaning every problem would already have people on it. Which means no problems for you.
Welcome to the market.