There are some commands I use very frequently that are not mapped directly to any keyboard keys without modifiers. It's hard to remember which key + modifier corresponds to which command and it's a lot faster to be able to press one key rather than hold a modifier key and press another key. The Data command should definitely be its own key (without a modifier) because a lot of the time I need to hold [data] and press another key or click something.
There are quite a few keys on the standard U.S. keyboard that have no hotkeys assigned to them. I propose mapping them as follows:
F10 data
F11 select last
F12 go to cue
` Undo
Scroll Lock effect
Pause/Break stop effect
[ +%
] -%
Insert Learn
End stop/back