Hmmm... In place of the 200% or 300% bonus on stats, it could be better to give a high bonus to defense, and a minor bump to offense. Say, 50% bonus to Defense, and 10-25% bonus to offense. If the battle ends and the Ship is still alive it keeps the bonus. There should be a limit to how many Ships in a Empire could get this kind of bonus, and maybe even impose a happiness penalty if the Heroic Ship is lost in combat , with the penalty getting higher for every great deed the Heroic Ship completes. That way you could simulate the population mourning the loss of their Heros.
Cool idea though
