In many RTS games, when you upgrade your armor, the damage you take is decreased by 1 per upgrade. This means armor upgrades are wonderful against units with low DPS, but almost useless against high DPS units. I would like to make the armor upgrades effective against all kinds of units, but since I'm not a huge RTS know-it-all, I don't know if there would be any balance issues or not, or if gameplay would be boring and unstrategic.
So please vote and discuss: Should armor upgrades decrease damage by a fixed amount, or by a percentage of the damage taken?