Predator + Tactician + Engine
Sure, most of those are NOT defensive upgrades, but the inclusion of stress giving out both arcs, boosting for positioning, and Predator to increase your offense allowing you to save your actions for focus or evade on defense is very good. These things all go a long way to making this ship live longer while allowing a much more flexible play style.
Also, Predator + Gunner + Engine allows you to take actions for defense and still have a very reliable fun, even if you remove engine it is pretty potent. Though it costs 3 more pts and doesn't let you use Stress mechanics to out play your opponent.