The following are a list of classes available in the Fulcrum ruleset, using my class design philosophy, along with the source material. New, rebalanced classes have the "fulcrum" tag listed as source. The Dead Levels link lists minor changes to some classes, often filling in "blank spots" in the class abilities list - levels where no new abilities are gained.
Ardent
Ardent is to psion as cleric is to sorcerer. Their power list is taken from their psionic mantles (like domains). They get up to 5 mantles, and each mantle also provides a special ability. The rebuild merges ardent with divine mind (a psionic paladin-like class that isn't very good, and is now eliminated) for psychic auras. We also bring in Dominant Ideal and Substitute Power alternate class features as standard features, and give them some bonus feats.
Barbarian
Borrowing some things from Pathfinder, the new barbarian gets some self-healing, damage reduction, altered rage progression, and new abilities called Rage Powers. I'm aiming to make the barbarian still good at smashing faces, but expand his repertoire a little bit.
Bard
The big changes to the bard involve making the songs scale more evenly, giving the bard choice in which songs he learns, and bringing the spellcasting into line with the other spellcasters (one spell known per level). He can cast cantrips at will, and gains some bard ACFs as class abilities.
Cleric
The Fulcrum Cleric has been limited two one spell known per level, and is now only able to choose spells from their domains, of which they get 6. Additionally, they get 4 Advanced Learning spells from which they can choose spells outside their domains. Channel Energy replaces Turn Undead so they can heal and deal damage without burning spells, and Cruelties/Mercies give them additional buffing/debuffing abilities. They get a few bonus cleric-centric feats.
Druid
The druid gets the same spell treatment as other casters - it is now spontaneous, has the sorcerer progression, and gains 1 spell known per level. Wild shape has been slightly nerfed, and it loses the animal companion - but can get a Wild Cohort with a bonus feat.
Fighter
The fighter gains a lot more flexibility by being able to swap out feats with 5 minutes of training, or even as an immediate action if he's willing to sacrifice a feat slot for the day. More feats have been given the [Fighter] tag. He also gains more skills, more skill points, Intimidation and Command abilities, and a few other class boons. Still not able to do EVERYTHING, but can now contribute meaningfully in a more wide range of situations, and do respectable damage and battlefield control.
Monk
Grafted onto the standard monk chassis are new Ki Powers, each of which has one continuous effect that can be expended for a more powerful one-time effect. The monk gains a dozen of these over 20 levels, and has a large list from which to choose. These abilities are usable any number of times per day, the monk just has to meditate to regain an expended focus. This gives them lasting power and versatility. They also get higher unarmed damage progression, AC bonus progression, and some new class features to round them out.
Paladin
Paladins can now be of any alignment except true neutral, and many of their class abilities depend on a chosen alignment. No daily limit on Smite any more, but it eats up actions. He gets a few auras as the Marshal, can choose either minor or major, and exchanges Turn Undead for Channel Energy from Pathfinder. He gets the best Knight battlefield control abilities (Bulwark of Defense, Test of Mettle), and his spellcasting is now spontaneous and Charisma-based.
Psion
The psion power progression follows the new one-per-level layout as other casters. In exchange, they get more class features depending on their discipline.
Psychic Warrior
The psychic warrior chassis resembles a worse fighter - less hit points, worse BAB, less bonus feats - but they more than make up for this with psionic powers, putting them at a loose tier 3. I've gestalted the standard psychic warrior with soulknife, by giving them Soulbond Weapons, thus eliminating the soulknife as a standalone class.
Ranger
Rangers pick up a host of new options, and the Scout class is rolled into the Ranger options, eliminating the need for a separate class and the Swift Hunter feat.
Rogue
The rogue gains more consistent damage through Penetrating Strike, allowing him to deal half his sneak attack damage to targets normally immune. This ability improves over levels, at first requiring a full round action, later a standard, then an attack. By level 20, he deals full sneak attack damage to such targets. The rogue also gains Intuition, which allows him to add his Intelligence bonus to a bunch of things. He gains a few defensive bennies, gets more Rogue Talents (one every level, and a larger list from which to choose), as well as the ability to trade them out. Finally, he gains some trapsmithing abilities.
Sorcerer
The sorcerer gets more limited spells known, and can only pick his main spells from one school (though they get a handful of spells they can pick from other schools). In exchange, he gets actual class features that relate to his chosen school of magic. This class replaces both the sorcerer and wizard classes.
Wilder
Wilder can be high tier 3 or low tier 2 normally, so they're in the sweet spot already. They get access to all the same powers as a psion (except discipline powers), but they get half the number of powers as a psion. I've adjusted the advancement of their Wild Surge and Surging Euphoria abilities a little and given them a few additional options. Surge Blast gives them an at will attack, Euphoric Boosts give them extra bonuses after they wild surge, the "Volatile X" line gives them new defensive abilities, and Artificer's Surge and Efficient Surge allow them to use their wild surge in new ways.
Alchemist (Pathfinder): This is a refluffed spellcaster that uses potions, extracts, and so on as their delivery method. They get a limited amount of spells known, but can choose from a good list. They also get to create splash damage bombs, which deal up to 10d6+intelligence modifier at level 20. They get mutagens which are self-only transmutation buffs. All of this means they are as good in multiple situations as a limited spellcaster. They only get up to 6th level spells though, so nothing game-breaking (though they do gain some things at a lower spell level than wiz/sorc). Healing, debuffing, battlefield control, buffing, damage, and more!
Binder (without online vestiges): Lots of options through your vestiges, but you can only choose so many tricks per day. Those tricks come from a pretty good list though, including skill boosts, spell-like abilities including save-or-suck/lose/die. They can copy abilities from other classes depending on the vestiges they choose (ie bardic knowledge, smite, sneak attack, etc). Most of the bet abilities are once per five rounds, which is limiting but at least let you get them off once per encounter or so. Also gets some good defensive abilities regardless of which vestige you choose, including immunity to fear, energy drain, and mind-affecting effects. The Improved Binding feat is basically a must-have. The Zceryll vestige gives them quite a higher power/versatility boost, so we'll be examining whether to eliminate or depower that vestige.
Crusader: The crusader is sort of the paladin/knight done properly. It is a tank gone beast mode. Delay damage for a round, which makes you better at attacking, and you can heal yourself. Heck, you can heal and buff others depending on your maneuvers. Good maneuver selection at that. Has some downsides - it isn't much for stealth, its skill list is not great (but still better than a fighter), and it's better off leaving social encounters to a different class (though it can try it, in a pinch).
Factotum: Can do everything, sometimes even better than classes that specialize (depending on your build) but more limited. Inspiration points allow it to tackle just about any situation, but you get a finite number of them. Can contribute meaningfully to any situation and fill in for any other role if the specialist is not around. Just a wonderfully-designed class. Again, if you want to play a better rogue, factotum is a good choice.
Incarnate: By switching around its essentia investment, the incarnate can be an amazing skill monkey. Soulmelds and binds give it some very good combat options, though it obviously isn't their strength (that would be the totemist's job). Incarnum Radiance is a decent buff, which by mid levels can affect the whole party. Prep time helps the incarnate, so they can choose appropriate soulmelds/binds/investments, but Rapid Meldshaping alleviates this to a degree. Binds screw with your ability to wear magic items, which is a notable downside. Still, this class can be useful in most situations, and great as a skill master.
Inquisitor (PF): Inquisitor is a moderately good combatant. It has a small but decent spell list. It has some similarities to a paladin but with more flexibility and power. I'm not as familiar with PF material as WotC material, but people tend to place this in tier 3 or high tier 4.
Magus (PF): The magus strikes me as Pathfinder's version of the duskblade, and so falls into the same tier. Channel spells through attacks for more damage, some utility, defensive, and debuff spells. It gets a slightly larger spell list, so in practice it may actually be slightly better than the duskblade, but nothing that seems game-breaking here.
Swordsage: This is a neat little class that takes some of the utility of a rogue and adds on a maneuver progression. It is a stealth martial class, and gets most of the best maneuver schools. They're good in an ambush, stealth, combat, dungeoneering. They even get the ability to teleport. Swordsage can also be a good replacement for a monk if you use the unarmed variant. While they are the weakest of the Tome of Battle classes, they gain the most supernatural-themed abilities.
Totemist: Totemist is the Incarnum melee class. Thematically it's like a druid that gives itself magical beast qualities instead of animal qualities. With its binds and soulmelds it can gain many different types of attacks and defensive abilities. It can invest essentia and its skill list is decent if not stellar. It doesn't have much in the way of social abilities, though, nor stealth, and its dungeoneering qualities come mostly in the form of dispatching enemies. It can gain interesting movement qualities with its binds, which can be a real benefit. These may be low in tier 3 or high in tier 4. They could use some small boosts to shore up their weaknesses.
Warblade: Warblades are possibly the best melee class ever. Want to play a fighter that doesn't suck? Play a warblade instead. If you need something killed, this class will kill it. They make use of a high intelligence, which supplies synergy with skill points. They improve in their combat tricks and gain a great list of maneuvers. They recover spent maneuvers just by attacking something. Decent skill list with some social skills, more skill points than the fighter. Like most martial classes, they are not much for stealth, though. They also don't have much in the way of ranged abilities, other than just picking up a bow and firing it, and they don't have a lot of ability to deal with traps and such, other than just smashing them to pieces.
Eliminated Classes
Archivist (HoH) - becomes an alternate class feature for Archivist
Beguiler (PHB2) - replace by Illusion Sorcerer
Divine Mind (CPsi) - merged with Ardent
Dread Necromancer (HoH) - replaced by Necromancy Sorcerer
Duskblade (PHB2) - replaced by Evocation Sorcerer
Erudite (CPsi) - replaced by Psion
Favored Soul (CDiv) - replaced by Cleric
Healer (Mini) - replaced by Cleric
Hexblade (CWar) - merged with Paladin
Knight (PHB2) - merged with Paladin
Lurk (CPsi) - replaced by Rogue; Lurk Augments available as Rogue Talents
Marshal (Mini) - merged with Paladin
Ninja (CAdv) - replaced by Monk and Rogue
Psychic Rogue (CPsi) - replaced by Rogue; Powers available as Rogue Talents as psi-like abilities
Samurai (CWar) - replaced by Fighter
Shugenja (CDiv) - becomes an alternate class feature for Shugenja
Spellthief (CAdv) - rolled into Rogue
Spirit Shaman (CDiv) - becomes an alternate class feature for Spirit Shaman
Soulborn (MoI) - merged with Paladin and Incarnate
Soulknife (XPH) - merged with Psychic Warrior
Swashbuckler (CWar) - replaced by Rogue
Warmage (CArc) - replaced by Evocation Sorcerer
Wizard (PHB) - replaced by Sorcerer