I find the more I play the more tired I grow of being entirely unable to defend myself when being flanked, which happens often in this game with the use of the cloak. Sure, I could run around with Proximity Alarm and Cloak Tracker, but that severely limits my mobility which is what I love most about Crysis. Some of it may come down to my awareness, but there's realistically no way to "out aim" someone coming from behind with such gratuitous aim assist...
So my thought is as follows (keep in mind this is using pre-hotfix numbers):
The Feline does far too much damage to be firing at that rate, and I think this is where your method of making Armor Mode reducing by a percentage a bit flawed. Using old damage numbers (because I have yet to see up-to-date numbers) the Feline does 20 damage up to 15m and around 17 after a drop off at 30m+. Armor mode reduces all incoming damage by 65%. So shooting a target with a Feline in Armor Mode reduces each bullet's damage to 13 up to 15m and 11 for 30m+.
The Scar, for example, does 30 damage up to 25m and around 27 from 45m onwards. In Armor Mode, it's 20 (rounded up) up to 25m and 18 (rounded up) onwards. Keep in mind, player health is at 120.
What does this mean? Well, the Scar loses 2-3 more damage than the Feline does while in Armor Mode. So you might say, "The Feline still does less damage than the Scar!", and to that I would say, "Thank you Captain Obvious!". What you have to remember is that the Scar fires at 700 RPM and the Feline at 1200 RPM. That's nearly double the rate.
At 15m, the Scar needs 6 bullets to kill a player in Armor Mode, and the Feline needs just slightly over 9. In the time you fire 6 bullets from the Scar, you've fired 10-11. All of this is assuming you are hitting the players chest, and only the chest. Headshots have a higher multiplier.
I'm not much of a math nerd, so I'd ask this to the community... Would it be detrimental to change Armor Mode from a percentage to a base number? Say to reduce all bullets by 10 damage. Maybe use a larger number for explosives.
Granted the tooltip doesn't need to state the base damage... Just a broad, generic statement for damage reduction...
Of course there is just the option of nerfing the Feline which would make a majority of this thought a waste of time... Either way, this post is mainly due to my boredom.