Autothrusters was likely made with the idea that it would be a type of 'fix' for arced ships against turrets. Thus it is powerful and cheap.
Since AT guarantees an evade (if the conditions are met), does it help set a likely price point for Lightened Frame? Lightened Frame also has a condition it seems: the attack dice probably need to outnumber your defence dice for it to proc. And if that is met, then you get to roll a (fickle) green die. Isn't this arguably weaker than AT, and so maybe cheaper than 2 points?
(Edit: typo)
Edited by J1mBob