I would rather pay gold for armor and have it permanent like camo.  Once you grind for a XI ship you will never run out of credits once you have mastered it.  I have unlocked 3 max ships on USN and working on the fourth and always seem to hover around 1 million credits.

Having to spend credits on armor is just a nuscience that will never deplete my credits which is why I think developers made expiring armor.

 The same could be said for airplanes and scouts.  Armor and airplanes should have a permanent gold equivalent.

Thank You.