Wow, this is such thorough feedback. Thank you! Thanks for sharing that link - that will be very helpful as we continue to balance this.
For the pipe breaking, there is a set number of pipes that will break during each wave/flight (it increases each flight). At the start of each flight, a random point in the duration of that wave is selected, and that's when the break is triggered. In the future, we might alter that so the same machine can't break twice in a row like that so that it doesn't feel like your repair is wasted.
For the SpaceBus Power bar, it wasn't explained super well in the jam version of the game, but it's a combination of thrust (% of working machines) vs weight (number of passengers) - so as more machines break, the energy will drop faster. But you can eject passengers to drop the weight below the thrust and make the SpaceBus power stop falling or start rising back up toward 100% again. In a future version, we'll make this relationship more clear.