Granted, we've haven't seen all skills but how is sneaking supposed to give you an edge in combat? A lot of encounters trigger from enemies that are initially pacific, and if your character is sneaking at the time, he will not be part of the combat.
To me sneaking feels like a way to steal stuff primarily but that would defeat the purpose of guerilla, a skill that just adds 50% of damage on an attack you're highly unlikely to land in the first place due to the nature of how combat is initiated and how sneaking characters aren't even included in it once it starts.
Thoughts?