That sounds like as harsh as the Treaty of Versailles to Germany.
While this would SURELY decrease it's massive amount of use in certain games/gametypes/by certain players (noobs), the tactical side of it might take a bit too much hit.
The worst ones, I think, are the changes to make it "grenade-friendly" (ie. Coming out of cover after a direct grenade 'splosion, Stickies are stickier).
Say you had full shields, and a grenade is thrown to your feet. You Armor Lock, but the grenade disables it, so you come out. Due to the new effect that is applied when you come out of it, you lose all your shields. It would be ridiculously easy to pick a headshot or simply throw a grenade and kill you. You had only wasted time, that you could've used to possibly kill the enemy and survive, armour locking, and therefore dying. On top of this, due to the radar and HUD loss, killing anyone after coming out would be quite impossible.
The other change, which makes you vulnerable to sticking, is easily pointed bad: Plasmas take 3 seconds to go off. While on armor lock, you're a sitting duck to the plasma-wielding enemy, and can not avoid it. The lock WILL go off before the grenade does. Boom.
I do think that it would be okay for the power-weapons to take it out on one blow, assuming that the player does not lose all his shields. That is, IMHO, way too harsh, and would reduce too greatly it's usability. Bleed-trough might work, too, though I think that field test would be more fitting to solve it.
I agree with the rest, I guess, even though it could be 3 secs instead of 2. Just sayin'.
Oh, and I'm kinda glad you brought this up here. Seriously, I think I might get an intelligent discussion, for change...