Predictions:
Luffy will become the Pirate King,
Zoro will become the World's Greatest Swordsman,
Usopp will become the Bravest Warrior of the Sea,
Sanji will find the All Blue,
Nami will make charts of the entire world,
Chopper will find a cure to every sickness,
Robin will read of the poneglyphs,
Franky will get Thousand Sunny through the entire Grand Line,
Brook will reunite with Laboon.
Otherwise there would be no point to the whole series.