Really, the entire point of the efficiency variable is REPEATABILITY.
The idea is that assuming the rest of the variables in your brewday are the same, then you can figure out the average efficiency of your equipment and process. Once you know that number, you know that the next time you make the same recipe on the same equipment and hit the same efficiency number, you'll have the same beer.
So at the point you are at, you really need to decide if you want to stick with your processes that produces a low efficiency, and just assume that low effiency when you are putting together your recipes, OR tweak a few processes in your brewday to get that average efficiency up a little bit, THEN lock in those processes and assume that average efficiency going forward for consistency sake.
If I were you, I'd try to get your average efficiency AT LEAST up into the low 70s before I dialed in your process. 9 times out of 10, a slightly finer grain rush will do the trick if you have that option.
Hope that all makes sense! Most people think they should be constantly striving to make their efficiency higher, and that's not really the goal, the goal is to have consistent efficiency.