Workers tech lead here.
On the first point: As others have noted, we're happy to lift the rate limit for any customer (not just enterprise). If a support person told you otherwise, I apologize! Please e-mail us and let us know who said that so we can make sure they have the correct info.
On the second point: You could always map your worker to "*", and then write JavaScript code that uses a case-insensitive regex to do the real URL matching. We've been trying to keep the configuration around Workers as light as possible since most things can be implemented in code in the worker itself.