I already sort of have them...
The Armor talents, if you have Armor, Light, you don't pay full price for Armor, Medium or Armor, Heavy. However, you don't HAVE to get the lower Armor talents to get the higher level one...
Plus we also have one or two talents that have prerequisites, so that would not be adding anything new either...
The thing to watch out for is for indepth trees, where you have to get half a dozen other talents before getting a certain one. So long as we are careful in that regard (I would put a limit of 3 levels on any "talent tree" type of thing), then that should be fine...