Years ago I coached a girls softball team, at the start of the year, in practices, all they wanted to do is practice batting, no effort at all in fielding practice. The first game they batted first, and rang up 6 runs, and were all excited, then the other team got up and promptly 15 run ruled them. I gathered them in the dugout, and asked them who thinks we need to practice defense? They all raised their hand. I said; I tried to tell you it doesn't matter how much you score if you can't stop the other team. Sometimes you just have to teach the hard way. We went on to finish second in the league only losing one other game. Balance is best, but if you have to lean, lean towards defense.