I am not sure if you own BigFix lifecycle but it could make your life easier with the feature updates or in-place upgrades. This will use all of the iso files in your image library and then allow you to deploy them without manually caching. One of the more powerful features of this is you can deploy the upgrade in check only mode ahead of time to check for errors. This will also precache the files on the machine to run the upgrade in a second step which will give a better experience for the end user. I did a guide on how to run in-place upgrades here -in-place-upgrades-brad-sexton/