I like the rules. Good job with the updated protect action, in particular.
The only part I have a bit of an issue with is the shuttle blocking rules. I think the rules language there could be clarified a bit - i find it a little hard to follow, and the part about placing the shuttle on the other side of the ships is a bit open-ended. You definitely need a rule like this to prevent abusive blocking. I recommend taking another pass at this part. I'd be tempted to eliminate any and all blocking effects for the shuttle. The shuttle token is flat cardboard, and ships could (physically) land on it the same way they land on asteroids. When the shuttle moves onto a ship, it may be possible to slide it under the plastic base, by tilting the base up one one edge, or removing the plastic ship base from the table momentarily, marking its position with a small movement template. You'd need quite a bit of rules language to describe that effect, though.