isn't that a definition of more damage
Against blocks, not against shields :p. And if you use missiles there's no difference since there's barely any damage lost already. So yea, it's like "more damage" even though it's actually less damage loss (more or less the same thing).
Missiles actually had the penalty reduced from 10% more power per output to 2.5%. I'm assuming that it's because missiles already had much better scaling. However, that made me wonder as to why cannons and beams were stuck with atrocious block removal scalability.
Tbh, modifying the power penalty won't really fix the problem because it's caused by the piss stream beams and bb gun cannons staying the same no matter the size. So yea, you're right, it's better not to change anything, which is why I was only suggesting.