The micro-usb port will fail over time. There is some hope with http://www.smk.co.jp/news/press_release/2011/934cs/ however adding a dedicated barrel type of connector would be nice. Speaking of improvements, the design of the ear bud base plate is awful. I have two of them and the ear bud plug on mine snapped in about 3 weeks, my girlfriend snapped her's off the first day she used it. I lumped up some epoxy around the connectors and that seems to be working OK.
Add a charging plug.