Okay, here´s my draft for a PC Were-raven race.  Some might object to the were-raven having three racial powers, but notice that, while in raven form, the PC cannot use weapons or weapon related powers and cannot use prayers or spells.  I think the power of flight coupled with weapons or magical powers would have an imbalancing effect.  Also, to counteract the power associated with flight and extra healing, I have allowed opportunity attacks and disallowed flight when bloodied.  I have not added any flavor text.
Were-raven (Corvanthrope)
  A were-raven always shape-shifts to the same humanoid form.  The humanoid form may be any PC race (with its associated size and speed), but the were-raven does not gain the special racial abilities or bonuses associated with that humanoid race. 
   
  RACIAL TRAITS
  Average length as raven: 28"
  Average weight as raven: 3.8 lb.
   
  Ability Scores: +2 Constitution +2 Wisdom
  Size as raven: Small
  Speed as raven: 6 squares if flying (terrain does not apply), 4 squares if hopping 
  Vision: Low light 
   
  Languages: Common, Second language of humanoid form and one other of your choice.
  Skill Bonuses: +2 Perception +2 Nature
  Corvum Constitution: You gain a +4 for saving throws vs. poison and disease.
  Selûne's Blessing: You are allowed two second winds per encounter.  However, any healing applied to hit point damage inflicted by silver, magical attacks or magical weapons of +2 damage or greater is cut in half and rounded down (i.e. 5 points of healing heals only 2 hit points of damage)
  Animal Agility: When in raven form, you gain a +2 bonus to AC against opportunity attacks.
   
  RACIAL POWERS
   
  SHAPESHIFT                         Were-raven Racial Power
  At Will:
  Standard Action
Target: Self
  Effect: You change into a large Raven or back into Humanoid form. The equipment wear or carry (but not creatures held by you) transforms with you.  In raven form, you retain armor class bonuses, but you may not use weapons, other than your natural ones, nor do you gain weapon bonuses for attacks. In raven form, you may not perform prayers or spells. You may not fly when bloodied. When you return to humanoid form you are stunned for 1 round, then dazed for the next round. 
   
  SUDDEN SWOOP                 Were-raven Racial Power
  At will
  Standard Action:
  Requirement: You must be in raven form and able to fly
Target: One creature
  Attack: Wisdom vs. Reflex (It is assumed that you are attacking the target´s head or sensory center)
  Hit: 1d6 Claw + Wisdom modifier damage. The target is surprised until the end of this round.  Whether you hit or miss, you may move the remainder of your movement rate after your attack, but opportunity attacks apply for the target and all adjacent creatures.
   
  BLINDING FURY                  Were-raven Racial Attack Power 
  Encounter
Standard action
Requirement: You must be in raven form and able to fly
  Target: One creature
  Attack: Wisdom vs. Reflex (It is assumed that you are attacking the target´s head or sensory center)
  Hit: 2d6 Claw and Pecking + Wisdom modifier damage and target is blinded until the start of your next turn.  On modified roll of 19 or 20, the target is permanently blinded.    Whether you hit or miss, you may move the remainder of your movement rate after your attack, but opportunity attacks apply for the target and all creatures adjacent to it.
  Miss: If the target has not had their turn this round, they move to last place in the initiative order for this round.
Heroic Feats
 
Selûne´s restoration
Prerequisites: therianthrope race
Benefit: Once per day, you gain regeneration equal to 5+1/2 level while bloodied. The regeneration lasts until the end of the encounter. If you take damage from a silvered weapon or magical weapon +2 or greater, the regeneration ceases to function until the start of your next turn.