Round convex mirrors should be fitted. Or at least that's what I'll be fitting. Perhaps I'll even stick a smaller extra mirror on the mirror itself (i.e. glue it to the glass surface) as some some touring motorcyclists do to have a better view.
Steering wheel: I like the matt black finish - Less reflections from the sun. Although I don't like it being branded and I'd prefer a wooden rim with those metal studs. But it should be possible to buy both of those things at several third party manufacturers.
Exhausts: Mine will be covered in black heat shield wrapping. But that muffler? I have no idea how this works properly, but I'd like it if it weren't placed at the very end. It looks like a stick with a thermos at the end.