Tom, as one coming from a lifelong background as a trad 88 note classical piano player, I can understand your concern, but when I transitioned from piano to arranger, I simply learned to approach 61 note arranger playing differently than piano. Because the left hand is typically dedicated to triggering chords confined within an octave and a half (C1-F#2) that leaves 3-1/2 octaves available for the right hand, which is only a 1/2 octave less than from middle C to the top of an 88 note piano. Consider that fact.

Tom, congratulations on your purchase of a Tyros 4. I'm confident you're going to really enjoy it a lot. I certainly am enjoying mine tremendously.