Ok, the more linear the results the more effecient, so landing right where you started is obviously the goal. Sometimes the quad/glute dominance is an issue and sometimes its not, but going straight up and down is going to give optimum results regardless.
IF YOU LANDED IN FRONT OF THE LINE-
Practice the top 1/3 of the jump, exaggerating triple extension, with special attention to the knee and ankle. Shoulders can also be an issue, so make sure to extend FULLY, and not what you THINK is fully. Think "reach backwards". If youre still landing forwards, try to make yourself jump backwards slightly, and up.
IF YOU LANDED bEHIND THE LINE-
Get into a semi goodmorning position (hips back, knees only slightly bent). Practice from this position over and over until you feel fluent with it, and are getting some decent height. Eventually add in a little more knee bend, without losing the powerful hip extension youve practiced.
IF YOU LANDED ON THE LINE-
Good job, youre doing it right.