Personally I found the old rule of fear more immersive (moral test before charge with a penalty in case of failure). Is there a particular reason for changing it (imbalance)?
I am considering playing a variation that would say "If you are meleeing a model with Fear, you must first take a morale test. If you fail, you have -1 to hit" to simulate reluctance and fear in the attacker's gestures (he trembles with fear and hits badly).
What do you think? Could this cause a problem with some units / rules?
One more roll, to simulate some effect, is immersive. But it drag the game. i know you would said: its just one roll! But the whole OldGame is a compilation of hundreds of great additional rolls.
I love OPG for how simply "crude" the rules are [Like WFRPG 1 ed , but i never read this book even]. Nothing is specified to the tiniest exceptions. And i think this are the main strength of OPR, you can craft it to your needs.