Here's my take on the sorcerer, using the Talents mechanic from d20 Modern. Seems balanced so far, and it's not as complicated to use as the variant bloodline sorcerers usually end up being.
Sorcerer
Class Skills: A sorcerer may add either Bluff, Diplomacy, Gather Information, or Intimidate to his list of class skills.
Skill Points at 1st Level: (4 + Int modifier) x 4.
Skill Points at Each Additional Level: 4 + Int modifier.
Spells: A sorcerer channels arcane energies.
A sorcerer cannot swap spells (as the rule presented in the core rulebooks), but he may upgrade a single spell with a higher level spell on the same path each time a new “spell known” slot becomes available.
(See
www.seankreynolds.com for details on spell paths)
Talent: At 1st, 5th, 10th, 15th, and 20th level, the sorcerer selects a talent from the following talent trees. As long as the sorcerer qualifies, he can select freely from any and all talent trees. No talent can be selected more than once unless so indicated by the talent’s description.
Arcane Power Talent Tree
Extra Spell: You learn one additional spell of any level that you can cast. You may select this talent multiple times.
Extra Slot: You gain one extra spell slot of the highest level you can cast at the time when you select this talent. You may select this talent multiple times. Prerequisite: extra spell.
Overchanneling: This ability enables you to fuel spells with your life force when you have no spell slots left. Whenever you overchannel a spell, you take a number of points of Constitution damage equal to the spell’s level. This ability damage can only be removed through natural healing.
Prerequisite: extra spell.
Sudden Metamagic: You may apply any one metamagic feat you know to a spell as a free action once per day per five class levels.
Prerequisite: any one Metamagic feat.
Battle Talent Tree
Increased Hit Die: Your class hit die increases by one step (1d4 to 1d6, 1d6 to 1d8). You gain +1 hit point per sorcerer level gained before the hit die increase. You may select this talent twice.
Armored Channeling: You gain Light Armor Proficiency. You do not suffer spell failure chance while wearing light armor.
Prerequisite: increased hit die.
Weapon Affinity: You gain proficiency and Weapon Focus with a non-exotic weapon of your choice. You may select this talent multiple times.
Prerequisite: increased hit die.
Weapon Channeling: You can deliver touch spells through a weapon you wield, provided you have the Weapon Focus feat for it or the weapon group it belongs to.
Prerequisites: increased hit die, Weapon Focus.
Familiar Talent Tree
Summon Familiar: All familiars grant +2 to Spot and Listen checks while they are within arm’s reach. The sorcerer is not considered to have the Alertness feat. Other familiar benefits are specified in the Player’s Handbook.
Augment Familiar: You add +1 to your class level when referencing Table 3-19 for your familiar's abilities. Furthermore, the range of effect for the Listen and Spot bonuses and spell sharing is extended to 10 feet. If you have more than one familiar, all are augmented. You may select this talent multiple times.
Prerequisite: summon familiar.
Extra Familiar: You can gain another familiar (although you must summon it normally). It must be a different creature than your other familiar(s). You may select this talent multiple times.
Prerequisite: summon familiar.
Improved Familiar: As the feat, but your sorcerer level is considered to be one level higher for the purpose of determining the type of creature you can select as your familiar.
Prerequisite: summon familiar.