domino said:
All stats can be powerful, or not, depending on the build.
Trying to make Charisma as important to a barbarian thug as Strength, or Strength as important as Intelligence to a wizard is stupid.
Making Charisma as important to a bard as strength is to a fighter, on the other hand, IS smart, and is more or less how things work out.
The thing is, each stat has a number of classes that need it to be high. However, some stats can be ignored by some classes, and some stats have use for all classes.
Strength: Melee-based classes have use for the combat bonuses. All classes have use of carrying capacity, though with bags of holding you can carry a lot of gear with only a moderate strength - hard to get by with a really low one, though.
Dexterity: Ranged attack is only useful for characters that want to attack from a distance. Skill bonuses are only useful for those classes that use those skills. AC, Initiative, and Reflex saves are important for everyone.
Constitution: No-one wants to have sucky hp and Fortitude saves.
Intelligence: Spellcasting bonuses are only useful to wizards and psions. Skill bonuses can be ignored by many classes. Skill points are useful for everyone, but of course some have more use for them than others.
Wisdom: Again, spellcasting bonuses are only useful for divine spellcasters and psychic warriors. Wisdom skill bonuses are slightly more generically useful than Intelligence skill bonuses, since everyone wants perception skills. But the biggie for generic usefulness is the Will save - paradoxically, most of the classes that want to use Wis for spellcasting already have good Will saves and don't need Wis as much for that.
Charisma: Like the other mental stats, spellcasting bonuses that are only useful for bards, sorcerers, and wilders. Some classes (notably paladins, but to a lesser extent clerics) have class abilities that rely on Charisma. Skill bonuses are only useful for those who want to get good social skills. As for generic usefulness... nothing.
This is why Charisma is generally the dump-stat of choice. All other stats have something to give to
every character: encumbrance, saves, skill points, hp. But a high Charisma doesn't help the fighter much, if at all.
I'd say that if you rank stats by their generic usefulness (meaning, useful to someone who doesn't go out of their way to make it useful) they come in this order: Con, Dex, Wis, Int, Str, Cha. This then becomes somewhat skewed by the number of classes that
do go out of their way to make Strength useful, so Strength is valued more highly than that ranking would make it appear.