I notice that when running a defrag, the program uses the end of the hard drive as a temporary holding area for files. I suggest, if possible, giving the option to use a USB drive (or secondary hard drive) as a choice for this. That way the program can be reading and writing at the same time instead of reading and then writing, thus making the program faster. At least that's how it works in my mind. Added bonus would be for it to check those drives and verify they have enough space available to do this.
Thanks for your time,
Jeremy