Just a thought - one that's been in my head ever since Kovid developed his editor and this one was bought back to life.
Merge Sigil and Calibre Editor's Reports into a single tool usable from either program via wrapper plugins - bit like DiapDealers' toolbox. It's 'annoying' having to dodge between them to get a report the other one offers - it also opens up the dangers of running two editors against the same source - concurrently.
FTR: 1. Of the differences between the two editors this is only one that 'annoys' me. 2. I put a high value on being able to jump from a Report line into the code, so, I'd wouldn't want lose that in a combined tool.
BR