Just to clarify, the penalty applies to units under an enemy FF too, right?
It seems a bit odd that a ship does more damage firing in from outside a FF than firing on something inside the same FF, or firing out from a FF, given that a FF is specifically designed to keep attacks out.
I also think that a ship that is already under the FF should be much more effective at killing the generator than it is now, whether just given a bonus or given a seperate health for FF and generator. If you're firing directly on the generator it shouldn't just be the same as the bubble soaking up shots.