The strait dope on Hull & Armor is found in Strategy sub forum, pinned post Combat Mechanics. Basically, I look at the research costs, especially the crystal. The crystal cost doubles for every level for why not balance both hull & armor. I need that crystal for planet improvements, structures, and research. Eventually it is needed for ships too.
---- copied ----
Armor
Armor decreases the damage received from attacks. Each point of armor reduces the effectiveness of weapons by a factor of 5%, however this is not a straightforward reduction. Instead it reduces the effectiveness of weapons by factor of 1/(1 + armor * .05).
<!--[if !supportEmptyParas]--> <!--[endif]-->
Another way of calculating the effect of armor is to consider each point of armor an increase to the base hull strength of the ship by 5%. However, armor is more effective than a straight hull strength increase because it increases the effective hull regeneration rate (again by a factor of 5% per point of armor).
<!--[if !supportEmptyParas]--> <!--[endif]-->
Example of Armor Mechanics
An Arcova Scout Frigate shoots (weapon damage 24) at a Kol Battleship (hull 3000, armor 5). The Scout will do 24/(1 + .05 * 5) = 19.2 damage. Ignoring all other combat mechanics, it will take the scout 3000/19.2 = 156.25 shots to destroy the Kol.
<!--[if !supportEmptyParas]--> <!--[endif]-->
Calculating the armor as a straight hull strength increase, using the same situation, the Kol Battleship now has an effective hull strength of 3000 * (1 + .05 * 4) = 3750. Ignoring all other combat mechanics, it will take the scout 3750/24 = 156.25 shots to destroy the Kol.
--- end copy ---