I used the Lurker only once so far--all of the characters wound up with at least one pact and Mary in particular seemed to abuse the hell out of it. (Heh). Now, I may have been using it wrong since she really did rock the game from the moment she picked up her first pact, but yeah, it definitely does make things easier.
I like the idea of not being able to spend Power in the turn you get it, but I also do agree that there are considerable punishments for having Power--or even for NOT having power since a handful of Reckonings force players with pacts to force other players without pacts to take them too. The Lurker, in my mind, is more about being used with the right people. It's very situational--if you use him as the Herald with a group that you know is cometitive or enjoys a little back-biting then he's the Herald for you. Otherwise, I would say just don't use him at all or go with the 'No power the turn you get it' rule instead. Maybe draw two Reckonings instead of one during Mythos? Or have a player draw a Reckoning whenever they make a pact instead of following the Herald card's instructions of only during Mythos or Spell Casting.