Decreasing the toughness of the planes would naturally alleviate the problem some. (I dare not propose that the effectiveness of the weapons ought to be increased

)
Also, the toughness of the planes can be debated more freely perhaps than the effectiveness of the guns. When guns are discussed people usually throw in the equation for kinetic energy and state that that is all there is to it (even though it _obviously_ is not).
However Funked has already mentioned that in his opinion the planes are already too weak (or the guns too efficient).
Thus, I can't really think of a way to make cannon planes less interesting (and still attempting to keep it all realistic) to use unless gun jams and such are implemented.
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SageFIN
"The wolves are gathering, the stars are shifting...
come, join us in the hunt!"
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