Hard to decide if this is a Sidewalk, or a Pedestrian area - its all kind of paved and merged together with the benches ontop of it.

You might be interested in tagging individual turbines (visible on digital globe imagery) - node/5008627113 is an example

With this, I traced roughly where the whole business is and moved the address/business name tags to that, left the building attributes on the buildings.

With a lot of these, I marked them as a delivery company office or similar

Fixed

Hi, welcome to OpenStreetMap :)

I changed this from a 'path' to a driveway, and added the houses either side.

You might like to add addresses on the individual houses instead of the driveway itself - that will make it show up in navigation apps and similar that use OSM.

The prision is available on digital globe, and appears substantially constructed now

Should probably be building=hospital if its still a hospital, or building = yes if its not anymore

This is actually Beech Avenue according to http://maps.sa.gov.au/plb/ (that is powered by the same data as is on data.sa.gov.au; which we have explicit permission to use)

I've removed this for now as it seems very unlikely to be an actual confectionery store

I've removed the service roads for now; we'll add a user note to recheck this when LPI imagery catches up to whats on the ground.

Unfortunately that's copyrighted / not compatible with the OpenStreetMap licencing.

SOme detail on it - http://www.haveyoursaywilloughby.com.au/gore-hill-exercise-equipment

I think its better tagged as leisure=fitness_station

You might be interested in https://improveosm.org/#background=Bing&id=w458133607&map=16.64/25.85501/-100.14083 - you can see a lot of roads in the new residential area

With the Dick Smith shop, shop=vacant might be better tagging

I've fleshed out some of the newly visible roads in the development via digitalglobe imagery, but if you are in the area and can survey the names of some of them, that'd be handy!

I added some of the roads being built visible in Digitalglobe imagery, but its far from well mapped. If you are familar with the area, did you want to have a look and possibly survey the current state?

With the playground on the beach, is that actually a playground? Imagery doesn't show it; and I don't recall seeing anything like that last time I was in that area...

With the buildings, try the 'S' shortcut to 'square' them (or right click, 'square') - can help get the edges.
You can also disconnect houses from each other if they "snap" together accidentally.