Combat and violence have been greatly clarified and simplified, replacing the old opposed roll system with a more intuitive "roll to hit then roll damage" system. Many edge cases have been smoothed out, and the whole thing overall is much better.

Health has now moved to a Wounds system, which is faster, more visceral, and much more evocative. Taking damage isn't just about losing abstract points, it's about suffering specific injuries that tell a story and prioritize quick thinking and difficult choices.

Armor is no longer a save, but rather destructible Armor Points. Ignore any damage less than your AP, but if you take more damage than your AP, your armor is destroyed. Time to raid the nearby crew-lockers...

We've removed levels all together, and characters start off a little stronger and can increase their Saves through Shore Leave, spending time training, resting, and gaining new skills.

All the classes have been rebalanced and skill selection has become much more specialized. If you're the person who is good at First Aid, you kick ass at it.

The Stress & Panic system has been rebalanced (no more Heart Attacks after taking a couple points of Stress... those were the days). Additionally, we've added the brand new d20 Panic Die. This is a die you only roll when making Panic Checks, which speeds things up greatly and makes Panic Checks a lot easier for new players to understand.

We removed a lot of weird edge cases to the rules and streamlined how combat and violent encounters work, removing a ton of rolls and vestigial nonsense.

A lot of quality-of-life changes have been made to the text, mostly in how it's explained and presented, to make it easier to understand for beginners.