Currently AV grenades do as much damage, minus proto, as AV weapons.
I feel it would be better if they were a compliment or a supporter to AV weaponry.
Change the affects:
Have it drastically mess with vehicle controls/camera/mobility.
Or have different affect on different vehicles.
Tanks: Reduce turret turn speed/ blind or "fizzle" the zoom camera,
LAVs: Reduce speed by a ton. (More than half)
DSs: idk what for this. Ds are already so sensitive.
Maybe for all of them-
Reduce reload speed of modules by X% for X seconds.
Maybe make the turrets be affected in different ways.
Railgun ruins zoom camera.
Blaster ruins slows turn speed.
Missile ruin accuracy.
(All of the above are simply options of many that could exist.)
Making them compliment weapons rather than being weapons would force players to spec real AV if they want to be AV.

Should still do a small amount of damage.
Not enough to really kill a tank even with 3 people spamming, but enough to hurt and make the tank buzz off.

Nay, what you speak of is the roles EWAR will fill, AV nades need to be a deterrent, enough to stop tanks and LAV's from getting too close. They should not be as effective as swarm launcher.

Everything you have suggested would make tank drivers kick and scream like a child that doesnt want to go to the dentist
I support your ideas

Tank drivers tend to do that, ignore them :P

The only real way to deter an LAV is to destroy it, since otherwise they will just roll over you and get rid of you

AV grenade says: "You are the Juliet to my Romeo. I cannot help but be attracted to your fine figure. We should be together forever, in death. ... ... ... I lov----" *EXPLODES*

AV grenades should do enough damadge to cause major headaches to most LAV's. If av grenades only mess with controlls and such there would be no reason to carry them unless you plan to hunt vehicles. If we made av genades the way you suggested there wouldnt be a reason to not constantly run around in a lav since the grenades would do nearly nothing and conversly the game would switch to everyone either being in a lav or being outfitted with anti armor.