One of the key elements to cost savings in the cloud is ensuring that you are not utilizing compute or storage resources when they are not required. Policing your utilization requires some diligence and Netflix recently released their Janitor Monkey tool which can assist with this. Coupled with this would be comparing your usage with current price plans from your cloud provider as they likely evolve over time. It can be easy to put your services in place and forget to ensure that you are only paying for what you actually need over time. Your engineering staff may not be the best group to perform this function (and you should not distract them anyway). Consider adding this function to your financial organization responsibilities because you may be able to incentivize their interest in this area. Doing this would likely require some amount of training and familiarization with with how to monitor utilization and match that with current price plans but the result may be worthwhile.