Another idea would be to make the turrets small rotating blisters with a barrel or two protruding out. The closest visual I can use an influence for this would be taking a look at the laser cannons aboard the Corvette (not the two Dual Batteries mind you).
I agree with this idea, making them small enough as to barely see them from a distance, thus keeping the smooth circular form seen in the movies. Also, we´d have to agree on the exact number of turrets we should use and general positions.
Also, I have to check on the poly count, as far as I´m going I could very well end up over 80K!!!!
By now I´m on 65K, having done some more greebling on the engines, but I think I could just lower the count only by reducing the amount of the smaller blisters.
Perhaps twikling again the small details, but as things go, I can´t imagine this model with less than 65.000 polys, (triangulated and with LODS).
EDIT: This picture here is to show my idea of where the primary cannons could be.
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