i m a bit torn about cap armour 8 ( i got utterly sick of trading when i got me one ) ... so on the one hand, i think whoever has it - deserves it. - on the other hand, it seems "reasonable" on a 750 million ship ( well, not reasonable , but as reasonable as is ) - while it "feels" somewhat wrong to slap it on a ship that costs only 18 million.
a gunboat without armour is still an awesome ship - like most capital ships ( except battleships ) it relies mostly on its 140k shield anyway, once the hull takes damage, the captain usually starts to panic a little. all in all, i think its no big deal. - if the enemy bomberpilot is lucky, it makes a difference indeed, but other than that, it just takes alightly longer with armour than without.