Hey Rails.

Yes, all of the places you mentioned are good. Just depends on the wind as to where will be the best spot. The lake to me typically has slightly less wind as it is a little more sheltered than the beach, however, there is no real swell in the lake making the lake an easy choice when it's too rough at the beach. Most Newcastle kitesurfers are on a Facebook group page called NEWKS so perhaps join there and someone will definitely help you out on the day as to where is the best spot.

Cheers.