The damage from the war cry should be increased (maybe I can). But since it's an AoE, it's still better not to increase it too much.
The sorceress will slow them down, especially the red ones, and the knight will kill 500, and even the black ones ;)
Although, I'm all for this ability.
Regarding the deadly strike, again, if the stack of ranged units is comparable to the stack of melee units, then it will deal 250 damage per hit, so it's an analogue to the simple double strike ability. The fact that small stacks of ranged units (relative to the target) are dangerous is true, but even more dangerous are small stacks of casters, such as sorceresses.