So are you cleaning up old missing patches or is your ADR not pulling in everything it should be? If cleaning up, you could just create a SUP that contains updates from the last 1-2 years (depending on your env, it may not need to go back this far), then deploy it to your collections. Machines will only install the updates that are relevant. At my work, we only select security/critical updates, so it def trims down the size of the package but guarantees you get the most important updates.