Any way you can add functionality for me to enter all my preferences, style techniques, html tag techniques, etc. and then have Sigil just fix all the books for me the way I would have done it manually? Perhaps save all of those preferences as a profile...so that I can switch all my preferences with a dropdown. Oh yeah! and perhaps have that profile preferences be exportable in a csv file.
Of course, along with that, we'd need a watch folder so I can just drag an ePub into it and it's auto-magically fixed.