Just simplify as follows :
Once the gust has made the airplane depart, arresting the roll rate is half the job. Reverting the roll rate is the other half of the job.
Airbus does the first half for you. The second half is up to you.
As for the C* law, if you ever notice your airbus not holding exactly exactly level flight while you're decelerating or accelerating, just know it's expected.
Regarding the OP question about longitudinal gusts (having an impact on lift in a symmetrical way), I never noticed the same thing as with roll. 'Theoretically' according to airbus lie about the pitch law being a load factor law, yes, but knowing the real equation, no.
At approach speed, the law equates maybe to a law that's a quarter load factor and three quarters pitch rate. I never noticed the quarter load factor part.
Maybe airbus test pilots do, when they compare with other laws, but we don't really get to do that.