now that i think about it, this thread baffles me. yeah, shadowdancer needs a buff, but I have NEVER seen anybody ask for a primal avatar buff. t5 PA is (IMO) worse than shadowdancer. just food for thought, but a discussion for another day....
Primal Avatar definitely needs a buff as well. One big difference though is that the main audience of Primal Avatar are Druids. They typically focus on Draconic Incarnation and Exalted Angel for their destinies right now and don't lose too much out of it, since their spells get pretty buffed out of it.
The problem here is that Dex based Assassin/Stealth characters have no other main options to choose from. There's always Fury or Dreadnought.. but that doesn't really serve the theme and only aids in either damage or DC.
IMO all destinies should be both viable and preferred for their intended purpose.