Yeah, it is quite effective.
It does give away a lot. I agree with you about the possibility of misdirection.
However, from early on during The Force Awakens, there has been a belief by a good percentage of the fandom that Rey would turn to the dark side.
You can see Kylo hesitate about attacking his mother's starship. Pretty cool.
Now we know how the helmet got smashed from the teaser trailer.
Kylo has some sort of "bacta bandage" to try and heal his scars rather than floating in the bacta liquid. Who knows? Maybe he does both.