One of the little features of Resharper I like a great deal is the 'problem bar' (I don't know the proper name for it) next to the scrollbar which gives a code reviewer a nice 'at a glance' overview of the code quality. Makes it nice and easy to check compliance.

Obviously, NCrunch is surfacing coverage info using a different metaphor, but having a visual cue on the class / struct declaration line (perhaps a coverage percentage metric or just a colour - although that might be confused with line coverage) would be useful.