I don't need more then 61 keys in arranger mode, and when I play the piano voice in full keyboard mode, I hit the octave button. But, moving the octave feels strange to me, but I manage. I would prefer a 76 note keyboard, so I wouldn't have to use the octave button, and feel like I'm playing in the wrong place. I don't usually play arppegios, so Moving the octave down is an acceptable compromise.
Starkeeper