Start a scheduled scan when one has been missed
Sometimes my machine is switched off or hibernating when a scheduled scan is due. This appears to lose the scan entirely. This brings two suggestions:
1) If a scan is lost because the machine is switched off, to start a scan next time it is restarted.
2) If the machine is hibernating or asleep when a scan is due, wake the machine up to perform the scan and (if this is possible) return it to its hibernation state when finished. I don't know how easy (or even possible) this is in the various operating systems that you support.