The biggest change in this update is not actually the shields turning red as ships take damage, the biggest change is that all ships and all projectiles have been slowed down by 20%, with according decreases to acceleration and turn rate. The objective of this is to incentivize players to spend resources on ship upgrades more than just on weapons as well as decrease the relative speed of ships approaching from opposite directions.
There has also been more work done to make brightness levels more consistent across stages and across different visual effects.
Now the main menu will have new bosses appear only after they have been defeated in the game.