The rate limit is there for a reason. The service is designed for real time retrieval of data as it is required, not for the collection of large data sets and, in order to provide this free service efficiently and ensure that all customers get equal access to the data, we have to protect it from excessive use.
However, we do have some leeway around the rate and the period it is measured over so I will arrange for someone to contact you to discuss how best to satisfy your requirements but, to manage your expectation, we are unlikely to increase the rate limit to the level you indicate, although they may be other ways we can help you.