I honestly can't even think of a serious DT era question for Derek. If I could, it has probably already been asked. Such as:
How did you mend fences with John Petrucci?
I know Petrucci played on a Sherinian solo CD, so it probably centers around that.
So not necessarily DT related:
Have you considered putting out a video on sound sculpting some of your favorite and iconic patches?
What about a video on songwriting / composition (not scales and exercises)?
How is Tony MacAlpine doing?
Still working with Albert?
Other than touring and recording with Van Halen, if you could make an album purely for your own self interest, what would it sound like?
Ever worry you might be exposed as a nice guy and not the egomaniac image you work so hard to cultivate?
Hoping and wishing good thoughts for your immediate family.