The requirement for partners to make requests when necessary is because of potential misrepresentation - your site would be powered by Skyscanner, but the data displayed would frequently be stale because of your cache. This will lead to a loss of confidence from the end users if they constantly access data which turns out to not have a relevant ticket at the advertised price. We at Skyscanner are constantly doing our best to maintain the balance of feasibility, viability and accuracy of 3rd party data, and we hope you understand the necessity of disallowing caching of your end.
If the rate limits are an issue, then you are probably generating a lot of traffic, which is great! Please contact us to review and potentially revise the limits, which we can consider after analysing the quality of your traffic.