They should reinvent their approach to handheld package design because honestly, whose hands have 90° angles in them?  The square iterations of the GBA and DS really bother me.  Not just because of how they're uncomfortable, but because Nintendo made, what I think, is the best controller ever with the GC controller.  It's just so perfect and comfortable ergonomically, so they're clearly aware of how to design something really well to fit into a person's hands, and they just don't seem to care to work that into their handheld designs.  If there's one thing I want more than hardware, software, or motion controlling, it's just to make it fit well in my hands.