The way that armor works in elemental has become a bit of an issue, previously it was attack being too good, now the balance has shifted the other direction. This is a tough balance to get right, there a many variables to look at. On the offensive side you have, strength of the unit, weapon stats, on going magic effects, etc. On the defensive side you have, dex of the unit, avoidance (aka dodge value), mitigation (aka armor/shields), on going magic effects, etc. Between these sides, you have the pieces of the puzzle that can be used for either side, such as terrain, number of actions per tern, direct one-time/short-duration magic effects, etc.
The problem with defense is centered around how you choose to defend. The two main paths are Avoidance, and Mitigation. If either of these are too high or can get to very high levels, then players will soon focus on those specific stats/techs/upgrades to the exclusion of the other. Take the game in its current form for instance. Mitigation value is far too high, thus players focus on getting defensive upgrades and completely mitigating weapons of lower tech levels. However, if you let avoidance get too high, then you end up with a 'luck of the dice' scenario, where people focus on it because it's the best way to stop damage, but when you get hit, you get crushed. A few lucky hits in a row could kill a unit that would normally be fine. Players don't want either of these scenario's, no one wants to be invulnerable (its boring) or an enemy that is invulnerable, and no one wants a situation where its completely random if your going to live or die.
The suggestion I have for mitigation is this: Have an armor system based on diminishing returns, soft capped, interdependent with the tech level of the weapon attacking you.
Let me break this down.
Diminishing Returns-Soft Cap: Each piece of past the first, should add less protection than the last piece. Lets say for example, the first piece of armor you put on adds 25% to your mitigation, the next piece adds say 15%, then 9%, then 5.4%, then 3.2% till eventually your soft capped at around 60%. You'll argue, that you can only put on 5 pieces of armor currently (or however many it is), but I suggest that each time something is added to mitigate your damage further is subject to this same principle. Spells, special abilities, armor... Lets say you have a spell that gives you one armor upgrade, if your target was naked, it would grant 25% mitigation of incoming attacks, pretty good spell, right? That same spell added to a full plate wearing tank might only add 3.2% mitigation. These diminishing returns would offer you some very interesting choices strategically and tactically. Do I get an army of highly armored costly units and not get as many protective spells? or do I get cheap units with fast movement and lots of sight range, but offer them the protection of my spells?
Interdependent with tech of the attacking weapon: The obvious argument to the diminishing returns-soft cap system is, after you hit the soft cap, why bother getting anymore upgrades? That is where this point comes in. It's ridiculous to assume that a set of padded armor is gonna give you the same % of mitigation against all weapons, a enchanted great sword is gonna cut through your padded armor like butter. However, a crudely made knife probably will not. on the other hand, is that crudely made knife going to be completely ineffective against someone wearing full plate? Is there no possible way that knife could ever damage the man inside? There are cracks in any armor, weak points, things that can be exploited. The answer is, equivalent tech weapons and armor should be 100% effective to one another. That great sword is gonna cause damage to the guy in full plate, but that plate is gonna hold up pretty well against it.
Separation should happen like this:
--Each tech level a weapon is above the defenders armor tech, should reduce the mitigation soft cap by 10%. Thus, a tech level 5 weapon hitting a target with a full set of tech level 1 armor, would be 90% effective.
--Each tech level a weapon is below the defenders armor tech, should improve the mitigation of the soft cap by 5%. Thus, a tech level 1 weapon hitting a target with a full set of tech level 5 armor, would be 20% effective.
This would allow all units to be able to damage all units, but to a significantly reduced or increased amount based on tech level. HP would go hand in hand with this, a low hp, low armor target is not going to stand up to much very long. A high hp high armor target is gonna stand up to a lot of punishment.
The issue with avoidance that's is so hard to deal with is how random it is. If a unit could hit you for 10,000 damage, but you avoid it 95% of the time, eventually your gonna die, with no way to predict when. This is the reason that mitigation is so much more popular than avoidance. With mitigation you see your hp bar go down at a predictable pace, you can make tactical and strategic choices around mitigation. The way that avoidance works currently, you cannot. I suggest that you have Avoidance work in a similar fashion to mitigation, but have it apply to different types of units.
Making Avoidance similar to Mitigation: I would suggest that avoidance work like this, for each point of avoidance you add, you get double that change to cause a 'glancing blow'. A glancing blow would act sort of like mitigation, in that, if you were unable to avoid the attack completely, then you could have it hit you at a reduced effect, say a glancing blow was 50% mitigation. Avoidance would have to be hard capped at 30%. If you were unable to avoid the attack completely and you were unable to make it a glancing blow, then you would be hit, and your mitigation would would kick in. If you were an 'Avoiding' type unit, you could have up to a 60% chance of having the attack be glancing or avoided, but after that point, you still have the protection of some mitigation.
Tying this into other parts of the game
--Avoidance could be tied into Dex by saying you need X amount of dex to reach Y amount of avoidance, with 30% being the hard cap.
--Avoidance could have a limit to the number of pieces of armor you could wear before it becomes detrimental. So 30% is the hard cap, but you lose 5% per piece of armor past the first.
--Armor could be tied into Str, saying you need x strength to wear Y number of pieces of armor.
--Magic could play a part in both, but go beyond the limits of your character. So Lets say your strength allows you to have 3 pieces of armor equipped and a magic spell gets cast on you to count as one more piece.
Implementing these suggestions would open up a wide range of choices for unit composition. Do I get a fast army of nimble ninja's? Or do I go with the tried and true tanks? Both choices are viable. These would also require that you keep up on the tech track both offensively and defensively. Maybe tie magic attacks into this, where a high avoider could avoid magic attacks, and a high mitigater could reduce the effects. These could help diversify your heroes, are you creating a hero that's got high magic and is a good avoider? or a strong character with high hp that can withstand alot of punishment? Strategically what do my resources support?
Anyway, this was a fun way to burn some time at work!