Revert the base changes to a Reaper's life force consumption rate and the damage buffs. Then introduce a new Reaper grandmaster trait called Perilous Strikes. The trait works as follows:
Your shroud attacks do more damage and your life force drains more quickly.
Server: Sorrow's Furnace
Guilds: [DOA] Descendants Of Ascalon, [LOOT] Legendary Order Of Thieves
Characters: Black Hooded S\D Thief, Celestial Herald & Power Reaper