Steve,
Number one is great drum kits, that sound live--my pet peeve. T4 is an improvement, but there is still room for more!
Registration system could use updating, with option to call up registrations numerically. You have to go through too many steps to make changes and save them.
Copy Korg PA3X songbook and Roland Chord Sequencer.
Full time volume sliders for style parts and lead parts.
Two XLR mic inputs, at least one with phantom power.
A smaller footprint. Tyros has WAY too much wasted space. You can't even put it in a 61-note bag, and it won't fit on a lot of stands.
Personally I prefer a Joystick to Wheels, but not a big thing.
Have the pads under the keys been updated? If you use a PSR for very long, it will need the pads replaced, regardless of how light a touch you have.
Ability to replace, delete, edit factory styles.
Tyros 4 vocal harmonizer is way better than the old one, but still a little short of Ketron, Roland and Korg.
Of course, hold on to the many things you've got right!
Thanks,
DonM