AussieBoo, you live in a fabulous city. Honeymooned there sometime ago and really loved the area. You have a nice house and yard to decorate.
I'm quite impressed with what you do already. Way more than I expected given that Halloween isn't prominent there. The windows looked great. That's something I like to incorporate too given I never know what the weather will be come end of October. I set up outside on the day of Halloween and guage what will go out that day. Pretty much everything outdoors comes down that night after the last ToTer has come by, which for us is about 8:30 or 9pm, and stored in the garage to be sorted out the next day. I think decorating that day keeps it special but it is alot of work to plan on that day and you're never sure it gets fully appreciated given the short timeframe.
8:30-9pm is quite late for darkness. Here we are still on daylight savings but it gets dark much earlier. Until this past year we had to contend with a fairly bright street light so did have some of the same issues creating a spookier atmosphere (the new LED streetlights actually are great for halloween now). These would be my suggestions:
*If you can invest in some colored lighting for some of your displays I think it would still yield a desired effect during the waning daylight and for sure later at night. Some of the LED lighting we have here is very vibrant, even some of the colored florescents do a nice job. If you don't have stores carrying this, check the internet for shipping to you.
*you have a
wonderful white fence area that screams decorate me...or project on me at night.
I see the fence as the foundation of some "building" for example--with several framed arched window silhouttes, turret, or props--appearing above at the fence line...ie a castle wall with dragons or a wizard peering down from above. Example of the dragon-- a foamboard or plywood dragon rigged with fog coming out of it's nostrils in bursts periodically (low-lying fog would work best)...that should gain you some more attention from passerbys. Just one example brainstorming here.
*You have a great porch area to use. If you could suspend something like black plastic sheeting, even cut into strips to move in the wind (if you pull on the strips they will get deformd and sort of look like drooping branches from willow trees or hanging seaweed -- see this from Martha Stewart:
http://www.marthastewart.com/271722/witchs-curtain ), from your gutters or between posts and I think you'd have a darker, scarier area for the kids to walk up to and get their candy. Given your porch posts, maybe you could even use a tarp with grommets on it and lash it to the posts to create a solid tarp wall of sorts. You could decorate the streetside and the porchside of it.
*Think of themes from Australian history/culture that you can pull from to make the appeal more local. Ghosts haunting a scene like Port Arthur maybe. Abandon ruins on an island with crocs in the waters and unfortunate escapees rendered to skeletons after an unsuccessful attempt to flee (sort of Island of the Dead). Occasional fog machine bursts might help create more of an atmosphere of a swamp area. And for sure the screaming sounds of tassie devils sends chills through anyone! If you can get one of those mean skeleton dogs like GrandinRoad sells (
http://www.grandinroad.com/small-skeleton-dog/halloween-haven/outdoor-halloween-decorations/681360 ), maybe it could double as a skeleton devil with some added growling/screeching sound effects in the background to sell what it's suppose to be.