Stronger and faster than the Punisher, and he gave Spiderman fits.  I believe what Praxis was going for was to give him a new edge with demonic slant, like the Inferno story line did with the original Hobgoblin and made him into Demongoblin.  Also Sin Easter was a former SHIELD agent.  Doesn't exactly put in the same skill class as Punisher, but that combined with super human strength and reflexes makes him challenge one on one for most heroes in the game.  Also he suffered from multiple personalities, but we could write it up to demonic possession.  There are some strong plot hooks there.