SoooShaded Respite: Works as endurance feat except it suppresses fatigue effects for failed checks for 24 hours. You take non lethal damage from failed checks normally you simply don't feel their effects, once you reach KO you immediacy fall unconscious.
Shaded Respite: You receive a +4 on constitution checks made to resist the effects of strenuous activity. You become immune to the effects of fatigue and exhaustion for 24 hours. You still suffer the nonlethal damage of strenuous activity.
Seems fine.Dark Resurrection: Allows you to use Resurrection as the spell. Must have the same material components.
If you want to flavour it a little differently though
My Soul for Yours: With a touch, you send your soul to barter the return of another. You raise a fallen creature who has been dead for less than 1 minute. Doing so is taxing on your mind and spirit and you suffer 1d4 Charisma damage and lose 200xp/HD of the creature you are raising.
I don't know how your group would feel about the possibility of every high level opponent they know carrying around a "1up", so I made this more restrictive version. Mind you it is by no means perfect, nor is my opinion.Me and My Shadow: An invocation which works as Contingency but only for other invocations. Must have the same material component focus only in this case it is a voodoo doll made of cloth, sewn gems, and stuffed with saw dust your own hair, nail clippings, etc. AKA "Die for me". Can be used to hold the material component for Dark Resurrection, thus meaning if you die it will resurrect you, or rather, die for you. Others can be made for specific people, like, your entire party. But only one at a time per person.
Cursed Dolls: You create a small, simple doll. You must place an item which harbours a direct link with the creature to be warded by the doll into the doll (hair, nail, blood, skin, etc). You may only have 1 doll/person, attempting to create another sets the other ablaze and negates its effects.
You may tie an invocation into the doll set to target that creature upon specific conditions set upon its creation (25 words or less). Doing so seals your usage of said invocation as its energies are focused elsewhere. Using the tied invocation destroys the doll.
You may channel beneficial or baneful invocations within the dolls. Once triggered, the material link is destroyed and allows your power to bypass the need for Spell Resistance or Saves.
Invocations that would require concentration have a duration of 3 rounds