You should consider that warlock cards are generally of lower quality than similar cards in other classes. There are many examples of this, e.g. Darkbomb vs Frostbolt vs Quick Shot vs lightning bolt. This is to compensate for the fact that warlock has arguably the strongest hero power in the game.
So directly comparing warlock cards to other class cards is not quite fair.
That being said, your example is egregious.
The example was fine the only difference is Warlock has heal synergy and warrior has armor synergy
Still 3 mana deal 2 to a single target is never ideal. You can target face though so I guess that's why it's 3 mana.