[IDEA] Different damage types
This has quite possibly been proposed already, but I couldn't spot it. If it has, this can be ignored.
Is there any merit to creating different kinds of damage? The example that comes most readily to mind is Starcraft, where most units inflict 'Normal' damage, but some inflict either 'concussive' or 'explosive' damage. In the case of the two latter, the size of the target affects what percentage of the damage is actually sustained by the target. Concussive damage deals full points to a small target, but medium and large targets only receive a percentage of that. Whereas explosive deals full points to large targets/buildings, but only a percentage to small targets.
This sort of system helps keep small units viable as the game progresses, and makes it possible to make highly effective defenses against certain attacks, without ruining the game-balance. To use Starcraft as an example, Terran Firebats (concussive damage) tear the hell out of little Zealots and Zerglings, but quickly become obsolete against later, larger units. Whereas the aforementioned Zealots and Zerglings can consider rushing a seige tank, since they'll only take half damage from the tank's 'explosive' attacks.
In that vein of thought, what if this game did something like defining objects as "Hard" and "Soft". Things like buildings would be "hard". Things like creep would be "soft". Certain attacks, such as the Rook's hammer would be more effective against "hard" targets, whereas attacks such as Reg's crossbow, would be more effective against "soft" targets. To use a popular gripe right now, Rook imba, making a target soft would reduce the damage it takes from the attack, whereas buildings (which have hit points to spare) would still take full damage.
It's not a critical issue at this stage, but as this beta progresses, game balance is going to become more and more important. This sort of idea might provide an option for balancing relative skills. Furthermore, once we get to play with generals, the ability to direct forces against their optimum targets could provide another facet of strategy to work with/defend against.
Just some thoughts.