This is probably less likely than an HDMI cable but how about they package in a wireless sensor bar? I've accidentally yanked the sensor bar down from the top of my TV more than once when doing something behind the TV and getting caught on that stupid wire. Probably not going to happen but it'd be nice.
I think it has to include a sensor bar and probably a remote, even though most people don't need them. It can't cost them that much more to add it relative to the increase in perceived value and though there are tons of remotes out there already, most are either regular remotes or regular remotes with wii motion plus added on, not the wii remote plus. And not including one would kind of seem like conceding that they expect not to sell them to anyone but people who bought Wiis.