There seems to be some confusion about cannons, so I figured I'd clarify some
aspects a little better here.

It seems to me that a class 2 and a class 6 have access to equally talented
crew; it's just that the class 6 can hold more of them. Therefore, they can
man more cannons effectively. That is to say, a class 6 ship with a fully
maxed out set of cannoneers using one cannon is wasting almost all of its
available talent.

Therefore, the advantage the class 6 gets is in sheer number of cannons. Thus,
the 'cooldown' period comes into effect - while you can fire your cannons
continuously, with a smaller crew and fewer cannons, you are firing any
particular cannon more often, means you're pushing your crew harder, means
you're more likely to have problems. Note that the misfire chance never goes
all the way down to 0, but it does get pretty low. So, class 6's become the
baseline for ideal firing frequency, with 5 (now 6) sets of cannoneer
quarters... you can do the math from there

Finally, I'll re-emphasize the range property... a cannonball with a base
range of 5 (hint hint) gives just as much accuracy penalty for being at range
2 as it does for being at range 8.

Hope this gives some insight,
Melemkor