I liked the Leia scene and I read it as intended: Leia instinctually acted to save her life with the latent powers we know her to have. Maybe the moment was too contrived or the execution a little funny, but it worked for me.
It was a bit out of place, she probably would of died in the explosion and would of exploded in space but who cares it was a way they could keep her alive.
People don’t explode in a vacuum. That’s a movie cliché that has no basis in reality.
https://www.youtube.com/watch?v=Q26aM-ZJFO8
tl;dw: It is theorized that the human body can be subject to the vacuum of space for up to 3 minutes before the subject dies. The main sticking point with TLJ is that the skin and organs should swell a lot. Not 1990’s Total Recall levels of swelling, but still a highly significant amount (like 2x normal size). Also there is a high likelihood that the subject would simultaneously pee, poop and vomit due to digestive gases trying to escape.
Once the person returns to a pressurized environment, they are likely to achieve complete recovery depending on how long the experience lasted. This assumes, however, that the subject doesn’t purpose to hold a full breath of air in their lungs, whose pressure difference would likely quickly kill the subject.