This is a collection of thoughts about shield and armour mechanics in Naev. It tries to identify a problem and discusses potential solutions.
The thing about armour
All ships in Naev have shields and armour in varying quantities. However, in near enough all cases armour is inferior to shields. The reason for this is that on one hand shields regenerate automatically and armour does not, while on the other hand shields completely prevent armour from being damaged in the first place. It is thereby evident that shields are preferable over armour.
In conclusion, then, armour has little in the way of a raison d'etre. Everything armour can do shields can do too, and shields can do things armour cannot. If armour is to be a valuable asset to a ship, this situation needs to change.
As per the above, our purpose is to make changes to the behavior of armour and/or shields that make increasing armour a viable way of increasing survivability. Below are some ideas to that effect. Not all of these are compatible with each other.
Changing absorb mechanics
Currently all damage a ship takes is mitigated by the ship's absorb value, no matter if that damage is taken by shields or armour. A viable and relatively minor change is to only use absorb for armour whereas shields always take 100% of the damage.
The effect of this is that armour, effectively, lasts longer under fire given the same amount of health. By itself this doesn't change much, it only functions as a health multiplier, but overall it is a step in the right direction.
Armour's Achilles heel is its inability to replenish itself (by default). This makes it an anomaly, as every other resource at a ship's disposal replenishes automatically (actually this is not true - missiles are also limited. However, "recent" thinking is tending toward auto-replenishing missiles as well).
The obvious solution is to introduce regeneration as a standard feature of armour on all ships. Of course this needs to be handled delicately. Armour should not end up being a second layer of shields, nor should the Soromid ships, whose major selling point is their regenerating armour, lose their advantage. One possible way to achieve the former is to limit armour regeneration to prolonged periods of non-combat. Armour should not regenerate if the ship is taking fire, even if that fire is stopped by shields. It should also need a certain time of not taking fire before regeneration starts, and require much more time to replenish than a shield. The second issue can be solved in various ways. Soromid armour could regenerate at a much increased rate, for instance, or it could recover in non-standard ways such as maybe "eating" another Soromid ship.
As stated, shields will currently prevent any and all damage from reaching armour until the shield is exhausted. However, if we change shields to become permeable in some manner, then armour becomes acutely relevant to continued survival. A ship with heavy shielding could not last long if its hull was made out of paper.
There are multiple ways of going about this. Firstly there is the concept of purely ablative shielding. In this scheme armour becomes the only form of health a ship has, while the shield essentially takes over the role of the absorb mechanic we have now. Such a solution seems to have little going for it however.
Another approach is to allow shields to leak damage through to armour. Possibly all shielding is imperfect so a portion of all incoming fire will be transferred to armour. Or perhaps the effect scales with shield strength, where the shield will begin to leak damage to armour if it falls below a certain strength. With permeable shields it becomes almost inevitable that armour will take damage, and that makes armour strength an immediate factor for survivability.
This idea takes the position that armour and shields are both health, but shields represent "short-term" health whereas armour represents "long-term" health.
In essence, shielding should be dramatically lower in capacity than armour, perhaps as much as an order of magnitude. In battle, shields can be easily depleted, but armour must be worn down by sustained fire. However, if the ship should evade fire for a short while, the shield will be able to fully reassert itself.
The effect of this is that armour becomes the primary health statistic for any ship, and shields represent a relatively small "free" buffer on top of that. In combat, shield strength is expected to fluctuate wildly, dropping fast as fire impacts the ship, then recharging back up during an evasive maneuver. Armour, on the other hand, is the measure of how much longer the ship can keep up the fight.
In this manner, armour and shields can be equally valuable depending on a ship's other attributes.