I agree with Yammahopper, Sense Ambush (along with all the uber-specialized situational awareness skills) needs to go. Alertness, the general subconscious awareness of your surroundings should be used in all of these cases. The only thing I would think modifies this, is specific professional mods and/or talents, like fighters getting a +30 to Awareness when in combat, a rogue gets their bonus when someone tries to sneak up on them or palms a knife, etc...
Marc R: In all cases (I believe) only Alertness is acquired through racial templates, never Sense Ambush. Usually it is 2 ranks, as well.