In addition to seeming rather overpowered, It seems to me as though the Dexterous shifter is underpowered compared to the other two. It has 1 good save and 3/4 BAB, while Con gets 2 saves, and Str gets a save and full bab, and its aspects seem to not be all that amazing (flight is ok, and the critical upping is nice, but the others get HUGE bonuses to grappling, intimidate, bull rush, charge, fast healing, DR, etc)