The reason that the level cap is so low is so you cannot max out all trees. It adds a decision making process to the game, and it also increases the replay value, to try new styles.
Great game, my only comment: I wish that there was some value in a mission to using a suppressed weapon well. Maybe a stealth level or the ability to face fewer men if you act quickly before they can fire. But great game!
 "Wizard's Run"){kind=icon}
 "Sierra 7"){kind=icon}