1. They are fun, but a Terran crew is still necessary.
2. They are not, under any circumstances, to be treated as a human.
2 there is not a value judgement. AI are not human, and any attempt to treat them as such is doomed to severely diminishing the value of 1. The Terminator gets away with being pretty human (c'mon guys, we all watch it mostly because it has Arnold Schwarzenegger blowing things up) because it's violent and homicidal and has awesome one-liners. Ultron is awesome because he's almost-but-not-quite the same as us... He's fully sentient, and displays emotions, but he just doesn't give a damn about humankind, and so he decides to break the planet.
These two Side Stories, ? and ! (the names are binary for those characters) are examinations of that. ! examines how the Terrans in this universe have structured the AI that they have, and compensated for their immense fear of it. Aetna is very human, but he has a mental block that keeps him that way. ?, however, is much more alien-the D were likely created off somewhere in a Gray Goo scenario thousands of years ago, and have been evolving ever since. They communicate like we text, and have a distributed consciousness, capable of absorbing parts of their fallen comrades.
I like writing nonhumans. It's probably one of the 'artsy'-est parts of my writing. I hope that's not a bad thing.