Not bad, though I'm not looking for a new bike solely because of the commute. I also want something I can take out on weekends/longer distances if the mood strikes me, hence the search for something a bit lighter.

For what it's worth, I plan to keep the mama-chari as a beater bike for short errands, and to get to the station when I have to take the train. As safe as Japan may be when it comes to crime, I'd rather not leave a noticeably different and distinctly new bike sitting unattended in a public place for hours on end.