I object to MijRai's contention that +1 to all defences is more reasonable than +1 to armour. There is no situation that I can think of (other than maybe a surprise attack or Lethal Weapon-style weirdness) where armour will be better than defence.
Indeed.
Defense blocks shifts on the attack and can prevent a hit. Armor blocks shifts on the attack, cannot prevent a hit, but reduces the effectiveness of a hit (reduces weapon rating).
So, if an enemy has a weapon 4 (supernatural strength and fists, say), and rolls a 5 to hit...
1-4 on defense before +1 bonus, then +1 defense gives 4-7 damage, and armor +1 gives 4-7 damage
5 on defense, +1 defense gives 0 damage, +1 armor gives 3 damage.
6+ on defense, then it is 0 damage.
So +1 defense IS just better. Remember too that if you have roughly equal defense and offense, the equivalent to "5" above is a substantial percentage. Also, the +1 defense adjusts one of the bellcurves, skewing the likely match-ups in a highly favorable manner.
The reason why armor seems so good as that it is often something free that doesn't depend on raising a skill or the like. It is a great thing to complement a good defense since it makes attacks that hit less potent, but by itself armor isn't that great normally. Defense bonuses typically work to replace a skill roll (e.g. blocks), rather than complement that roll. Just about the only ability that adds to defense are the Speed Powers. Armor, on the other hand, inherently works by complementing defense rolls, which is why magical items providing armor halve the strength of the item for the armor rating and defensive items do not.
In other words, block X is not like a bonus to defense at all, it is a replacement to defense. Armor X (since you have no natural armor from skills) IS just like +X armor. This is why armor looks so nice in the game, because it is dang hard to raise those skills higher and armor uses a non-skill system. When comparing simply +1 bonuses to existing stats though, armor IS worse than defense.
