Arguments against the cheapening of a very, very weak

1) Chains-of-attack Breaker. Very rarely useful, because:
a) Small character with powerful Chains-of-attack (I recall only - Marchosias and Marrigan (at that, she has immune).)
Rayne, Veronica, Iosara, Lilith, Griever, also possess chain attacks.
b) Cost 3 AP does not allow to do additional Dodge in case of failure (Players prefer a more stable version - basic Dodge from each attack in Chain)
It depends, sometimes a character has already activated for the round, but not spent their AP, and the opponent attacks with them with their last character, almost no reason NOT to counter-attack.
c) "-2" Penalty - very strong surcharge. Example: Mean value Basic Attack = 5. Mean value Basic Defence = 9. In case of successful Dodging and after attack, The attacker hit the target only for 6+ at d10 (att 5(-2) vs. def 9) (and this if Defender non Dodging).
Since the Defender is being attacked after they have spent most of their AP, the odds are good they have no AP to dodge. That said, Counter-attacks are extremely strong on certain characters, particularly high base damage and/or Critical Mastery using characters.
2) Empire-style ability.
I long time play for Empire. And I often better not to Dodge, and even more so to pay a huge price for the dubious bonus from Couterattack.
Very few character's in this game can choose to forgo dodging, even in Empire. The primary problem Empire has to overcome is bypassing the enemies' dodge. Utilizing Counter-attack on a high damage Empire character with Critical Mastery tends to cause respectable damage.
and for the record, I have been playing Empire since this game started.
3) "Changing cost would really devalue those units with special counters, unless you want to go around and reduce there cost too".
No. Special counters usually provide benefits commensurate with its price. Change in price will lead to the rationale behind the price of everything Special Counters.
Example:
a) Special Counter Kronen has = 1 AP for Dodge, 1 AP for chance Attack (with "-2" and 1 AP for bonus +4 att/+2 dmg. And the player will have a choice between simple and special Counterattacks action. All logical.
b) Special Counter Rayne = 1 AP for Dodge (and she has 10 def!) and 3 AP for: "+2" bonus and FOUR attacks (6 att/2 dmg or (on the chance of Master Couterattack) 8 att/2 dmg). Amazing skill for amazing cost. All logical.
c) Special ability Elhaim. It does not see the game. One small correction in text ability "Defensiv Mastery": Perfoming basic Counterattack cost is reduced by one Action Point). As a result, the character will gain buff, which will bring it to the level Arias and AlDjinn (and still up to them, it will be too far).
That will still lead to all of those skills being devauled, since they were costed with the 3 AP cost of counter-attack in mind. Just because they get additional benefits doesn't mean they weren't intended to be as cost efficient as they are.
4) "It may lead to defensive wars where both sides are sitting in defensive waiting for riposte".
No. It may leed to slightly more frequent use of this ability. It's no secret that most players prefer to spend a very strong attack (10+ att with bonuses) and Defender rarely in the best situation.
Actually, the odds are quite good that it would turn the game into a counter-attack war. Attacking out of activation is a very significant benefit, especially when the enemy has just spent their AP attacking themselves.
Defender is usually at an advantage in most situations as it is, unless significant buffs are utilized on the Attacker. Only Critical Mastery really defies this trend, as Defense is on average higher then even Special Attacks.
----
Counter Attack isn't meant to be commonly used, it is a very situation specific action that can be quite powerful when used at the right time. The buffs it received with the arrival of the Saga 1+2 rulebook were enough to satisfy me, the chance to break Chain Attacks and ignore the -2 Attack penalty on a 10 are quite useful.