Yup that's actually a tradeoff you have to consider in the game, putting more power into the engines speeds up how long it takes to make an FTL jump. So if you don't think you can beat the ship you're fighting, it can make sense to put all power into the engines to try and jump away before they destroy your ship. Turning off life support still leaves you with the air currently in the ship which lasts for some amount of time depending on how big your ship is/how many crew members you have/how many hull breaches, open airlocks, or fires there are.

Yeah, life support being off or at reduced power would mean carbon dioxide build up and it would probably get a bit sweaty, but you can survive for quite a long time in a sealed room, especially with how much spare space is in Star Trek rooms.

Unless life support includes something like "shields that keep all the air in" or something.

I agree with the theme of the post, but some of the examples need more work, possibly at the expense of being less quippy