^
3. Possibly, but I'm not sure. I'm still having a hard time believing the Clairvoyant has legitimate precognitive abilities. If he did, he wouldn't need to read Coulson's mind to find out what happened, he could read Fury, the Doctor, Agent Hill, etc.'s mind.
You are confusing telepathy and clairvoyance. The Clairvoyant can see people's action (accept Coulson) but I don't think he can read people's minds. Which brings up an interesting point. The Clairvoyant must have seen SHIELD's resurrection technology but it seems there is the more to Coulson's return than simple tech.
Update, Just watched "The Magical Place" and Raina implies that Clairvoyant can read minds or at least sees people's dream. Either the Clairvoyant has multiple powers or the writers don't know the difference between reading minds and seeing the future.
Planets are detected indirectly - their influence on other celestial bodes are noticed and their existence inferred from there. If Coulson cannot be directly detected by the Clairvoyant, his presence could still be detected based on the actions of the people around him.
There can be a third option regarding the Clairvoyant either having multiple powers or the writers not knowing what they are doing - The Clairvoyant could intentionally be giving misinformation to his followers like Raina. Or she misunderstood the Clairvoyant's abilities.
My guess is that her hacking skills are somehow related to whatever it is she can do. I guess we'll have to find out.
How would a newborn baby demonstrate hacking abilities out in the middle of nowhere? Even if that were the case I just can't see that as a credible justification for wiping out a whole village and hunting down the Shield agents that took her.
In the Marvel Role Playing Game, Reed Richard's abilities at invention and creating new tech was a super power in addition to his stretching abilities.