I agree with you on the number 2 and 4, however, I'm not so sure about number 3 (1 has a 50/50 chance IMHO). But I do believe we're going to see a new F-Zero game for 3DS from either Shin'en or Next Level Games (they might have hinted at it with "they keep giving us better and better IP"). I also think we might see Miyamoto's new IP, but it won't be with Retro, it'll be developed in-house. I believe that Retro has been keeping themselves busy with one of two things: A) a new entry into the Metroid Prime/First-Person Metroid games (but it won't be nearly as dark as Prime or Echoes); or B) a possible reboot/new installment in the Star Fox series.
EDIT: I didn't specify a platform for F-Zero







