The following observations are of course my personal view and do not claim to be the “truth”!
Here comes Liu Kai (Poland):
- very good overall fitness and good footwork
- quite choppy and consistent backhand defence
- good forehand topspin on pushes
- good return on serves with his backhand usually with long pimples
- good occasional deceptive float when defending on his forehand side
- forehand countertopspin too inconsistent
- forehand defense still often too high
- never using long pimples to defend with forehand
- not showing a great variety of serves
- not using the full potential of the long pips for “messing up” the game such as aggressively pushing the ball on serves or pushes from the opponent
- get greater variety of serves
- practice forehand counter topspinning also with lots of sidespin
- practive flipping to pushing the ball aggressively with the long pips in order to make it more difficult for the opponent to get in with a first rocket topspin
- (okay you can’t be an “as” in every regard, that’s true) but maybe try backhand blocking with pips in occasionally or backhand topspins against pushes to get more unpredictable.