Generally, the more weapons the better, I think.
Of course, it was a lot more annoying to add multiple weapons back in my day. I've never used a power ship with more than 25 weapons. I might be wrong on this.
You use only 1% accuracy because the power a weapon generates only depends upon attack, not accuracy. (Or something like that.) Basically, anything you put in accuracy is wasted as far as power goes.
Oh, and I would strongly advise against using less than 8 weight in a weapon. In fact, there is no real reason to go with any amount other than 8 weight in a weapon, unless your ship has less than, what, 20 space? Something like that? Anyways, I justify the number 8
here.
If you put a 8 weight weapon on the pship, that would mean additional cost of 1155 (7*165) cr per ship.
If you make 1 million of these, that would mean an additional 1.155 billion cr. The same billion I could use to make another mission ship.
Edit:
Here's what I got after I plug in some numbers:
For 1 weight weapon, 17123 att at 1%, yielding effective hit rate of 171.
For 8 weight weapon, 37443 att at 1%, yielding effective hit rate of 374.
That means, a cost of increase 1155 cr per ship, the effective hit rate goes up 203 point.
203/171 = 1.187 or a 19% increase.
In other words, if the pship worth more than 6078 cr each, using an 8 weight weapon makes sense.
If the pship worth less than 6078 cr each, it is advisable to lessen the weapon weight.
And the impact isn't that immense, really.
For example: A decrease of size from 8 weight to 7 weight requires 1000 LESS en cost, which translate to output of 333 LESS att power, and at 1% accuracy, the effective att yield is only 3.
Yes, you read it right, only 3 less att yield per ship !
Referring to the above figure of 374 effective att yield per ship, 3 is less than 1%. But the saving is huge in comparison ---> 165 cr per ship !
Even in a one-million pship configuration, the total effect of 3 less att yield is still less than 6 million att yield.