well water or no water, 90 destroyers is very extreme. I could stomach 20 terran destroyers before the NTF war (though that would be a lot) as you see at least half a dozen of them. And I think that if you were to count up the destroyers that actually appeared or were referenced in FS2 you would find at least a dozen. However, I would definately say that there should be at least 2 corvettes, maybe 3 or 4, to every one destroyer, and there should be 2 cruisers to a corvette if you are still using them. And the mysterious "Frigate" designation... I've yet to see it incorperated into the FS designations with any reliability. Explain their role a bit more before we can give you an estimate on how many your fleets should have.