From my experience, a low level pusher is a hacker... he doesn‘t have any more of a good technique than the ball basher does. Both are doing very big mistakes technique-wise. The difference is that the ball basher is using mostly top spin shots, whereas a low level pusher rarely can hit any of it... we‘re talking sort. Of 3.0 players here.
From what I know, it‘s easier to take the strokes of a ball basher to make them consistent and decent than to take the strokes of a pusher to make them powerful and heavy. Pushers typically do not have anything ressembling a good form, whereas ball bashers are closer to it. Technique wise, it‘s easier to improve a ball basher than a pusher.
However, you need to know how to play a match to win it. Strategically speaking, it‘s not as bad to waste some offensive opportunities than to overhit. When you overhit, you loose the point; when you miss a chance to attack, you just give your opponent one more chance to win the rally. In that regard, a pusher might be more easily turned into a great tactician since he probably can switch more easily from fearing the mistake to being patient,, waiting for the right ball. The ball basher‘s attitude has to be changed as a whole to do the same thing... it‘s difficult.
As a whole, I‘d say it‘s slightly easier to turn a pusher into a great player than a ball basher. To me, one of the most fundamental trait of great players, what makes the difference between good and exceptional, lies in the players‘ head. The great player is patient, lucid and calm... everything in its attitude opposes him to a ball basher. Of course, strokes means something, but it‘s mostly about how you use your tools, not about which tools you have... unles two opponents are really not of the same level, it‘s the hoow which matters most.
" When I get sad, I stop being sad and be awesome instead. True Story." -Barney Stinson