I think I would remove:
caps lock (standard)
print screen (standard)
scroll lock (standard)
the entire numeric keypad (standard)
alternate functions for the "F" keys, so they're just F1-F12 again (non-standard)
F-lock key (non-standard)
My favorites (non-standard)
I would keep:
mute, volume up, volume down, play/pause (non-standard)
I would keep "back" and "forward"
I would have to look at what's left to figure out what would go where caps-lock was.. maybe home and end.
Then you would just have delete, page up and page down above the arrows, and media keys crammed in above that..
Much smaller keyboard and still great for my purposes without cramming things together and making it cramped.
If someone wants a numeric keypad, I would just buy a separate device.
Yeah.. I'm so going to have to get myself something that's 100% customizable if I'm ever going to get close to what I want. The problem is I really like the physical layout of the main keys on the 4000 pro.... Split keyboard with a slight seagull like affect.. Everything feels like it's in its most natural position.