Finally decided the tweak I want to try for Held: I've reduced the accuracy penalty considerably, the evasion penalty slightly, and increased the movement speed penalties significantly. It is now much more about restricting movement than anything else (though of course, at Held++ it still completely disables evasion.)
Changes:
Held 1:
Acc: -16 -> -10
Evd: -33 -> -25
Mov: -33 -> -50
Held 2:
Acc: -33 -> -20
Evd: -66 -> -50
Mov: -66 -> -100*
Held 3:
Acc: -50 -> -30
Evd: Cannot (no change)
Mov: Cannot (no change)
* - Remember, the wording is "slows movement by 100%". 100% slower doesn't mean you can't move, it means it takes twice as long.
While I was in the neighborhood, I changed Chill's movement penalty from 12 to 25, since 12% is barely noticeable.