Shall we think this through a little more?
Slice serve is sidespin, gives the curviest ball path, taking the player out wide the widest.
Top/slice goes in more often, can be hit HARDER and FASTER, but doesn't take the opponent as far out of court.
Normal slice also bounces lower, while taking the opponent wider.
Top/slice can be kicked up over chest high, right into the strikezone of rightie NCTA players.
Pure slice needs to be hit slower, because only gravity helps cure it in.