I cannot stop emphasizing these points of kirikaeshi. You hear me saying these a lot. You know why? Because they are important yet they are easily neglected when people get used to kirikaeshi.
There is no end to the kendo basics. The longer you study kendo, the deeper it gets. Having studied kendo more than 30 years (since 1980), I have never felt, even once, that I have done kirikaeshi right.
What you see in the video is very very basic. Once you have mastered the coordination, you will have to polish up your kirikaeshi even more.