As I recall, Savage Species assigns reach a +1 ECL in its own right, and I agree. Reach lets you get a lot more attacks of opportunity.
Mind, your Large orcs should possibly also be getting the usual ability score modifiers for the increase in size, just for consistency. Which would be another +1 ECL.
Umm, Savage Species has the Half Ogre with Large size, Reach , +2 total to stats (as opposed to the Orc's -2), and a +4 natural armour bonus, with a Level Adjustment of +1. So Savage Species doesn't really support your argument.