I think Tango's first observation is the most important one. OP is almost jamming the shoulder into head on shots. There is no way to be powerful or spinny or very consistent on anything stronger than a bunt doing that.
There may be reasons why, but also, OP is not using the legs and hips much. Even on shots Koreans call for using "short hip", there is a timing/rhythm to it and a minor explosion. I think OP could generate a LOT more power and spin, but is sequencing things.
Don't sweat it, just do your best to be loose and let each part of the chain sequence do its thing. Later, on some shots, you will feel if you got some or all of it right. From there you improve.Being loose is a base, later, when you have better feel and control over your explosion, you will know when/how to add more explosion.
Maybe if you quit jamming up your shoulder, the rest of it starts OK... but from the clip I see, OP is not initiating much energy with leg/hip. What little is generated, is getting stopped at shoulder.