Originally Posted by
Person_Man
Ninja is a nerfed class
The Assassin's Death Attack is a nerfed mechanic, because it uses a Fort Save (which is very high for most enemies) and its Save DC doesn't progress once you leave the Assassin class, making it even less useful in ECL 16+ games.
Improved Initiative is a weak feat, as are most other feats that provides a static bonus.
High crit weapons don't synergize well with Sneak Attack and Sudden Strike, because bonus dice of damage aren't multiplied on a crit.
The fluffy backstory sounds great.
So, are you willing to consider other build options, as long as it stays within your fluff. Or are you you wedded to some sort of Ninja/Assassin build using that particular weapon?
Also, what books do you have access to?