A Synthstrom Deluge arguably ticks those boxes, except perhaps for the "piano layout" (not that I think that makes much difference when you can't play either device like an actual piano, and at least the Deluge has a luscious isomorphic keyboard) and the large screen (though the screen isn't really the primary interface on the Deluge, taking a more supporting role of dynamic visual feedback to the real interface, which is pushing the physical buttons - you can get quite far on the Deluge without even looking at the screen.)