Re: Integrity stat
The Integrity or Barrier stat bar shown on the item card is the ‘base’ stat of the item, and then that value is multiplied by some value per the item’s level to get your total Integrity or Barrier. I believe there’s other multipliers as well with each individual armor class so it get complicated.
Plating and Modifiers affect the base stat and not the total HP of the item, and the change in the base stat is not multiplied by the item’s level.
You’ll notice your shield would have 600 HP normally, but is reduced by 60 when you would expect 90 if Hollowed Plating is a 15% reduction. It’s actually taking 15% off the base stat, so 400 * 0.15 = 60, and 400 - 60 = 340.
Re: 15% vs. 0.2%
15% is accurate, currently. The tooltips on many subsystems aren’t displaying or rounding correctly.