Yes, it's sci-fi, but there's still a bunch of implausible things happening here. Also, spoilers.
  1. Noise in space
    Right. Not so much.
  2. Drilling to the Earth's core would have repercussions.
    Earthquakes? Accidental volcanoes? Liquid hot magma? Dr. Evil had this part better.
  3. $100 million?
    Again, Dr. Evil errors. You can win the lottery for more. Bad negotiating skills!
  4. A bright white sphere?
    R you advertise your presence more than that, if you're 'super-intelligent'? Rookie mistakes.
  5. Every Judd Hirsch Part.
    What an incredibly dumb story arc.
  6. A retcon that undermines the existence of the first movie.
    (again, spoiler-y). If they're here for the earth's core, why bring an invasion force? Hmmm?