I think at some point FFG will come out with some kind of hierarchy where by you go through and identify each source of a characters Defence (Cover, Armour, Weapons, Talents). Second step is to add to those sources with only the applicable Defence Modifiers (eg; a crystal doesn't add to the defence of your armour) and then you end up with multiple defence numbers from various sources. Then the last step is a list of which sources can be added together to get to your final defence totals (Weapon and Weapon No, Armour and Weapon Yes?)
They could simply cap defense in general at 4 or 5 and be done with it. IIRC they have capped starship shields already at 4.
