In my limited experience Ted, if you are in Sydney / Manly I would stay there.
I have been visiting since 1981 for sailing on the Harbour side, since maybe 1998 with wife and kids staying on the ocean side.
We stay at the (I'm struggling) Ocean Royale ( maybe) apartments on the ocean side.
Last year in end of June / start of July we went up for a week to show French exchange student Sydney.
She loved it!
Enough surf to amuse me, and great to see lots of kids out further north.
End of year sports dinner for Sports Captain daughter at school had Layne Beachly as guest speaker, she suggested no need to go further.
Learnt her surfing there.
I love Manly.
Images ended up way out of order.
Dinner at the Manly Grill worth the trip if nothing else,
Daughter on the left as images have loaded.