OK, make the bezel turn on the iPad when you double-tap anywhere on it. Or shake it a little to turn it on. Or say "iPad ON" to it. Or using ASL sign for "O" in front of the camera. Or since it does predictive text so well, just improve that so the iPad itself simply predicts from your usage patterns when you want it on and turns itself on then. Or etc..But not everyone uses a smart cover.
My point? Surely someone at Apple is smart enough to come up with a way to eliminate the hard HOME button and still let users easily turn it on and off.