For 6 consecutive brew sessions I have made sure that the sparge took at least 45 minutes and I have improved my efficiency percentage from 68 percent and below to around 74 Percent, once getting 76 percent. I think 74 to 76 percent is a reasonable goal for my system and I'm glad to be achieving this range consistently. This is important because I can now write recipes with an exact gravity in mind and actually hit the target without making adjustments like malt extract addition or an extra long boil.
The final product will be more predictable as well. Malt additions might get you to the right gravity but they mess with (sometimes badly) the flavor profile of the beer.
Yesterday's American Pale was designed to come in at 1.059. The actual gravity was 1.060.