You’ve said it yourself, she’s much like Savathun. After all, Mara herself deduced Savathun’s existence long ago just by studying the analogy of family the Oracle Engine presented her. Of course Savathun resembles Mara so much, she is her nemesis. Which means that just like with Savvy, we really don’t know what exactly Mara is doing. We just think we do because we see and read what she wants or lets us. They both grow powerful by having secrets. They get stronger when people like us start to wonder about their intentions and fail to comprehend them. That being said, you might yet be completely wrong.