I live near Sydney harbour, but can't see it due to lotsa' high & medium rise, so my version of winter might be your summer! My windows are locked open about 6", I don't have a heater, just layers.
Outdoor shop thermal tights (not the heavy ones), ditto long sleeved t-shirt, black cotton socks, often over a pair of black sandals, in wet weather walking shoes, long velvet skirt, merino & possum waistcoat made in New Zealand (in the 19th century someone thought it would be a Good Idea to import Australian possums!) On top either a good thick Scottish cardigan, possum/merino cardigan, or a light or medium down jacket.
If I'm cold in the evening I might wear both my cardigans
ps. I have neighbours & friends who use heaters & wear less clothing. My electricity bill is similar winter & summer when I use fans in bedroom & living room - 6" & 15" - to cool down.