Nth Stradie has easy access with car (via barge) or bike (via same barge) altho most spots u will need to catch a bus to the other side of the island e.g Cylinder Beach, Flinders or Pt Lookout but Pt Amity is close for walk or bike.

If you have a 4 wheel drive you can access approx 20+kilometers of beach from Pt Lookout to Jumpin Pin - this beach runs Nth Sth so any N / NE or S / SE wind works well also besides other wind directions already mentioned Jumpin Pin (end of the 20k beach run to the Sth) works on Westerly too which u are unlikely to get this time of the year tho...

Moreton I have not ventured to but I believe is more shark infested than Stradie altho I would keep my head up at Pt Lookout and the coast line (beaches) Sth to Jumpin Pin as they are well known nasty spots! If you going over with mates take a 4 wheel drive and explore Stradie it's awesome for surfing and fishing!