my main argument is that no fighter should be able to mount an oversized gun without having ti give up certain other aspects.
For example, a gunboat forward gun on a fighter would require an oversized generator which would directly have an effect on the drive systems and shields.
I'm sorry for being a bit "blunt", and borderline rude, but i think it's a valid thing to discuss... You can't have everything on one ship, even if it's a "super" version of something.