I wasn't talking about treason. In your post you said one faction will use technologies, and one would use magics. Suppose only the techno faction has firearms, this means that if you are in the techno faction, you will never face an enemy attacking you with firearms. Since anyone holding a gun is an ally. By the same token, if you are a magic user, you will never fight against a flag that uses magics. So the techno users will never need to think about defending against firearms, and the magic users never need to think about defending against magics. It may also mean that some artifacts are only useful for one side. Is this preferable?
Spies
On the other hand, double playing will indeed piss off many people. Probably won't implement that. Having spies alone is quite risky too, ideally, members of each faction should feel safe to talk about strategies. That probably won't happen, but at least the players shouldn't have to deal with the constant stress of being backstabbed.
So in this game spies won't be about deception. Probably would rather sacrifices this dimension to safeguard the overall trust and loyalty required for the Flag system to work. It is important that the players in the same faction can trust one another.
So 'spies' correspond more to 'scouts' than 'traitors'.
Spies having skill of both sides is ok, but if spies are not played as traitors, then it probably won't be necessary.
Berserker
Delaying the damages taken is a good implementation. A similar way of implementing it is to increase the Hitpoint temporarily when the berserker effect is active, and have the added effect taken away when the berserker effect is gone. In your way, the berserker is invincible while berserked, so that will probably motivate the player to do some more crazy stuffs (suicidal attacks, since after activating berserker, the character has a 30 second of invincibility)
Damage Model
Damage model is always a difficult topic. In reality, human is very fragile. most high resolution damage models create a downward spiral (i.e. after you got hit the first time, your performance decreases, making you more likely to get hit again).
Note that there are already ways to slow an enemy down using magics, and the various debilitating magical effects already do what a higher resolution damage model can do.
Another related question is whether the combat should gear more toward skill-based or stats-based. The more skill-based it is, the harder it is to use tactics and strategies. It also make it harder to evaluate strengths of the different flags. But each flags can keep a win/loss ratio, so it should be implementable. Currently, combat is a mix of skills and stats, but skill does not correspond to hand-eye coordination or click speed. Skill correspond to positioning your character, your choices of abilities, and your timing in executing weapon skills and combos:
Combos:
1) Your fellow teammate unleashed a special weapon attack on the enemy, with the right timing, you unleash your special weapon attack to combo with it to deal bonus damage.
2) The mages begin casting a huge spell that takes 15 seconds to cast, the melee commander jumps into the enemy, and unleashes an area of effect weapon skill to freeze them and make them vulnerable to ice magics for 3 seconds. During those 3 seconds, the magic spells that took 15 seconds to cast land and the enemies get nuked.
3) The mages begin casting in battle instance 2 between the city wall and the siege weapons. Catapults in battle instance 3 fire. The magics in instance 2 adds to the catapults shots and turn the shots into fire dragons, and direct them to hit the city gate in battle instance 1.
- FlagA in Instance 3: Yo B, blizzard incoming
(Translation: enemy mages started casting the nuke 'blizzard' from instance 3 to instance 1, these are long range nukes, think battleship)
FlagB in Instance 1: we are ready, tell us when
(FlagB is going to counter it by using the combat mages to form a reflective dome)
FlagA in Instance 3: fire in the hole
(FlagB received the signal and the combat mages formed the seal. The blizzard shattered around the dome and dealt an AE damage to the enemies in Instance 1)
FlagB In Instance 1: OMG
FlagB In Instance 1: that was tight, took screenshot
FlagA In Instance 3: neat
These are the types of tactics that can be implemented with the current damage resolution. It already take some coordination and skills. Note that these tactics relies on a certain level of deterministic behavior. Too much variables may also make strategies unreliable and turn the battle into chaos.
So my current position is to assume that the character have the high resolution damage model, and see what happens. My hunch is that higher resolution damage model is equivalent to a larger set of combat abilities. (i.e. the weapon ability Legsweep that induces a special effect is the same as hitting the enemy on his legs in a high res dmg model). The difference is in a FPS, there are no such thing as 'abilities', the only difference is whether you aim at the torso or at their leg. By selecting different part of the body to hit, you are selecting the different 'abilities'. This make the gameplay more hand-eye coordination type skill-based.