An even Darker SOMA [ending spoilers]

[Cranky Old Man]

Second: Why all the talk about WAU trying to get on board, or control the ARK?

The WAU's primary function is to preserve humanity. I don't think WAU interfered with the ARK project, because it also is a way of preserving humanity. Why would it need to stop/control something that fits within it's purpose? That's probably why it left it alone.

On a final note. We could see that WAU was getting better at keeping humans, human. It could be that it began to understand a little more about what 'preserving humanity' meant.

No, the WAU doesn't want to STOP the ARK. It'll launch the ARK. It just doesn't need Simon (or maybe even Catherine) to be on board of it.

The WAU doesn't mean conquering other planets with dragons as a hostile action. It's simply spreading humanity to ensure humanity's survival. ...only "humanity" in this case, is a bunch of brainscans, that I personally argue doesn't even have a real consciousness. It's death looking like life, made to sucker people just like The Thing. Imagine The Thing as being something that an alien civilization cooked up to preserve itself, augmented by an artificial intelligence into a being of perfect survival. That's what alien civilizations might be in for if they find this satellite, only this thing isn't even actually living itself.