Few more things:
let us schedule not just drives, but even folders (all files in a certain folder) and the reason to this is that I use my web browser almost all the time and its cache is always becoming a mess in less than a day. And by mess I mean 300+ fragments in 10-30 MB files. Scheduling defrag on the whole drive is taking too long because it's a big partition, but defraging those cache files is taking like 1-2 minutes. So an automatic defrag schedule in every couple hours would be great. Or as an alternative, after a certain amount of time the user is idle, an automated defragmentation would start (like screensaver).