Just speaking personally, but one thing I wonder about with the issues is putting aside the 'internet knowledge base' how much I've accumulated knowledge of how to gloss over all the little issues in windows that doesn't translate over, and whether that applies to other people in general. There's the common "I migrated grandma and pointed her at firefox and she's loves it" anecdote for users with little assumptions, so for different types of user it'd be an interesting project to catalogue what pain points they come across, major ones are likely well known but I expect it'd be really interesting to gather minor ones. How much is adaptation to the windows/linux "DNA" or ways of doing things that would cause breakage if they were changed and how much could be looked at by various projects.