I really want to like this, but it really does seem overpowered. At level 1 a Legendary Shifter has 3 natural attacks each doing 1d6 + Str mod damage, all at full attack bonus (so 3d6 + 3 Str mod total).
Compare this to a fighter with a greatsword doing 2d6 + 1.5 Str mod damage. The shifter is easily out-fighting the fighter, without even needing a weapon! And this is before even considering the cool array of shapeshifting powers the shifter gets.
I prefer the way the shapeshifting works in this version, but unless I'm overlooking something I don't see why anyone would ever play a fighter next to these guys.