I'm a Bondi local...it is always packed with people...if you're looking for a more chilled beach hang out, check out Tamarama, Coogee or Bronte beach, all 5-10mins from Bondi.
The trolley tour of Boston, offered as an optional, is the best way to see the entire city. Take it at your own pace, but I would suggest stopping off at the USS Constitution and Fenway.
German beer is all organic so you cant get hang overs - I dare you to test it! ;D
FYI - make sure you have cash ahead of time because they don't take plastic and there isn't an ATM in sight!