Barbarian needs more rage!
Core mechanics:
Rage. The basic rage can be started as a free action, lasts for 0 rounds, and does exactly nothing. You get to craft your own personal form of rage from a number of templates and effects, each of which can be further modified on the fly by spending fury points. Only 1/encounter initially, but at higher levels you can enter multiple rages at once, or consecutively.
Fury points. Whenever you deal damage or take damage, you gain one or more fury points. Your maximum fury and the amount you start each encounter with rises with your level.
Rage components:
Each component has a base cost in fury points, which may be positive or negative. Add up the total cost of all components used in your rage. The rage costs that many fury points to enter, and while enraged your maximum fury points are reduced by the same amount. If the final cost is negative, you gain the negative value when entering the rage, and your maximum fury is likewise increased.
Many components have an augment effect. While in a rage, you can spend fury points on the augment components of your rage. Except as noted, this takes no action. You needn't even be conscious. You can normally only spend fury points on augmentations during your turn. Track the total amount of fury spent on augmenting each component across the duration of your rage to determine the total effect. You cannot spend more fury points on a given component's augmentations than your class level.
Since the base duration of a rage is 0 rounds, ending instantly, you must select a rage component that alters its duration. You can only select one such component. Duration components are listed separately for ease of use.
General Rage Components
Brute Strength
Cost: 1 fury
Benefit: You gain a +2 morale bonus to your Strength score while in a rage.
Augment: For every 3 fury spent to augment this component, the morale bonus to Strength that it grants increases by 2.
Frenzied Grace
Cost: 1 fury
Benefit: You gain a +2 morale bonus to your Dexterity score while in a rage.
Augment: For every 3 fury spent to augment this component, the morale bonus to Dexterity that it grants increases by 2.
Furious Endurance
Cost: 1 fury
Benefit: You gain a +2 morale bonus to your Constitution score while in a rage.
Augment: For every 3 fury spent to augment this component, the morale bonus to Constituion that it grants increases by 2.
Berserker Will
Cost: 1 fury
Benefit: You gain a +2 morale bonus on all Will saves while in a rage.
Augment: For every 2 fury spent to augment this component, the morale bonus to Will saves that it grants increases by 1.
Whirling Frenzy
Cost: 3 fury
Benefit: Whenever you make a full attack while in a rage, you can make one additional attack at your full base attack bonus. If you do, each attack you make this round (including the extra attack) suffers a -2 penalty on the attack roll. If you make multiple full attacks in a single round, the penalty only applies once; it does not stack with itself.
Augment: For every 6 fury spent to augment this component, you can make one additional attack in this way. Each extra attack beyond the first made this way is made with a cumulative -5 penalty on the attack roll.
War Cry
Cost: 8 fury
Benefit: When you enter a rage, you let loose a thunderous yell. All opponents within 60 feet are shaken for the duration of your rage and take 5d6 points of sonic damage. A successful Will save negates the shaken condition and halves the sonic damage. This is a mind-affecting, sonic effect.
Augment: Shaken, frightened, panicked, and cowering opponents within 60 feet take 1d6 points of sonic damage each round while you are in a rage for every 4 points of fury spent to augment this component. This is a mind-affecting, sonic effect.
Instantaneous Rage
Cost: 1 fury
Benefit: You can enter a rage as an immediate action.
Penalty Components
Mindless Brute
Cost: -2 fury
Benefit: While raging, you cannot use any Charisma-, Dexterity-, or Intelligence-based skills (except for Balance, Escape Artist, Intimidate, and Ride), the Concentration skill, or any abilities that require patience or concentration, nor can you cast spells or activate magic items that require a command word, a spell trigger (such as a wand), or spell completion (such as a scroll) to function. You can use any feat you have except Combat Expertise, item creation feats, and metamagic feats.
Tiresome Rage
Cost: -1 fury
Benefit: At the end of your rage, you become fatigued for the remainder of the encounter (minimum 1 minute).
Berserk Assault
Cost: -2 fury
Benefit: You cannot voluntarily choose to end your rage, and if no enemies remain in battle with you while you are enraged, you must nonetheless attack the nearest creature to you (other than your familiar, animal companion, or other bonded companion) to the best of your abilities each round. A successful Will save (DC equal to 10 + the number of rounds remaining in your rage + your remaining fury points) allows you to end your rage voluntarily when the last enemy is defeated, but you only gain this one chance.
Reckless Rage
Cost: -1 fury
Benefit: You suffer a -2 penalty to your armor class while in a rage.
Self-Destruction
Cost: -2 fury
Benefit: You suffer 1d6 points of damage each round that you remain in a rage.
Duration Components
Short Fuse
Cost: 0 fury
Benefit: Your rage lasts 1 round.
Augment: For every 2 fury spent to augment this component, your rage lasts 1 additional round.
Lasting Anger
Cost: 2 fury
Benefit: Your rage lasts 3 rounds.
Augment: For every 1 fury spent to augment this component, your rage lasts 1 additional round.
Smoldering Fury
Cost: 4 fury
Benefit: Your rage lasts 5 plus your Constitution modifier (if positive) rounds.
Augment: For every 1 fury spent to augment this component, your rage lasts 2 additional rounds.