That's tough, I generally will play sneakier characters in most games so I went rogue first. It was fun, but I also really enjoyed druid.
I ended up choosing Moon Druid because the Wildshape was a fun wrinkle to use through EA, but I've enjoyed both of them. When I play again I'm think of trying either a Wizard or Cleric. I'm most excited to see how they handle Monk and Barbarians though!