I think the overhead is actually the most important shot in tennis. You have pros that have mediocre serve, forehand, backhand but ALL pros have EXCELLENT overhead. To be really good, you can get away with one or two mediocre strokes (mediocre but not sucking bad) except the overhead. You really can't go offensive at all if you don't have a good overhead. Even if you could get your opponent on the run and you are in command, you would lose that command in a sec if you couldn't put away a desperate lob from your opponent on the run. Even a the pro level, most winners I would say are overheads. So you see how important it is.