the north face of athabasca is an easy III; don't even try to argue that it is III+/IV. the rock step is one body length, maybe two, so it is at most 5m. barry blanchard re-rated the crux at 5.8/M4 this spring which is fair, it is like five moves to mantle up into the upper gully so pretty easy for the grade, especially with the fixed pins. the grade IV's in the rockies are considerably harder than the north face of athabasca; the shooting gallery is an "easy" IV and the crux is twice as long, steeper, and is very poorly protected except in the spring when there is ice to place screws.
you guys had about as good of conditions on the face as you can have; and i should know, i watched you climb.
edit- i should also mention that athabasca is in Jasper National Park, not Banff.