There are at least 2 ways the term "pushing or pusher" is generaly used.
One is as a type of stroke, the other is as a style of play.
As a style of play "pushing" is defensive, a kind of continusl resetting of the point, giving the opponent one more opportunity to make an unforced error. The style often lacks a perticular game-plan (other than outlast the opponent).
As a stroke, "pushing" is inelegant, decelerating, often unskilled or lacking fluidity, sometimes "ugly"( in a sense).
So, the opposite of "defensive", in this sense, is not necessarily "agressive" or "attacking" (though they may be included), but rather "constructive" and "active". Rather than waiting for the opponent to self-destruct the non-pusher is trying to open the court, make placements, create opportunities and win points.
As far as shot-making, the opposite of "pushing" might be accelerating through the ball, "hitting out", driving through the ball, and having a fluid stroke that is capable (in itself) of putting pressure on the opponent through pace, spin, or angle/placement.
So, 2 words "Active" and "Constructive" as opposed to "Defensive" and "Passive".