I want to say Reed for that one, he has the most heart IMO. Scotty is fun and all but as his brother, that'll get tiring, I'll tire of Picards lectures, and it feels like Miles wasn't a big fan of his family (non-immediate). Reed sounds like he'd be the best brother in the bunch.
Would you rather have Kirk, Picard, Sisko, Janeway, or Archer as your offspring?
I got Reed mixed with Tucker. Miles is my new pick.