A very nice PrC; I might have a use for this in my next campaign.

Just one nitpick:

Quote Originally Posted by Djinn_In_Tonic View Post
Walk with Death (Ex): Exposure to the energies of the afterlife have left their marks. Non-sentient Undead do not register the presence of a Restless Troubadour unless she takes aggressive action against them. She may resume or suppress this ability as a swift action.
You probably need to note for completeness that if you attack an undead, suppress the ability, and then resume the ability, the undead still perceives the troubadour; otherwise, you could pull some kiting shenanigans with a bunch of non-sentient undead.