So, a few suggestions to give the rogues some love:
Name : Skillful targeting
Requirement : 4 levels of rogue
Description: You are masterful at picking out and striking structural weak points on a body. Whenever you flank something that's immune to critical hits, you do 1d6 extra physical damage with each succesful hit.
Name : Skillful Dismantling
Requirement : 12 levels of rogue, Skillful Targeting
Description: You are truly a graceful demolition expert. Whenever you flank something that's immune to critical hits, you do 3d6 extra physical damage with each succesful hit.
The following should be one of those bonus rogue feats that you can get after the 10th level:
Name : Greater Weapon Finesse
Requirement : Weapon Finesse, Rogue lvl 10
Description: You have learned the art of striking quickly and decisively. For any weapons that could be finessed by your character, you use half your dexterity modifier ( rounded down) for damage, instead of your strength modifier.
Thoughts and feedback?