In real life spear offers tactical advantage, they have a lunge greater than other weapons but aren't easy to use in close combat so why don't apply the full damage in the game just for attacks that come from two tiles of distance and apply a scaled damage (-2 to damage?) to 1 tiles distance attacks?
Because that not only overcomplicates them and goes against the standard rpg vibe it also makes them insanely hard to balance as you would have to up the precise damage and fiddle the numbers for the lowering damage on a case by case basis.
