Hello,
if you're correctly positioned on the ball, the animations are almost identical. However, if you're far from the ball, or the ball is too high or low, then your player will adapt his strike so the ball will be hit with the center of the racket (most of the time). In TE3, the racket often didn't touch the ball, which for me looks very bad.

Also, the bone structure of the players in TE4 is slightly different, which slightly deforms the animations, so there's a tiny loss of quality from that.
Personally, I enjoy seeing many variations in the animations, to get feedback when my player has an issue hitting a ball too low, too high or too far : this is much more lively than in TE3 where the exact same identical animation is played whatever the situation is...
