Welcome Timbo!
I have a different type of scope so can't help you with collimation I'm afraid but would thoroughly recommend you find space in your calendar for treating your eyes to one of the regular observing meets in the Sydney area - take a look in the Star Parties, Clubs and Community events section. These typically happen around New Moon for best contrast for DSO viewing, so in about 2 weeks from now and roughly every 4 weeks.
The objects you mention (with the exception of maybe C93) are all quite low in altitude at this time of year and especially in the Sydney area are swimming in the atmospheric soup. Objects in Sagittarius and Scorpius are best left for a while, but come winter they'll be in prime sky real estate bang overhead where you're looking through the least atmosphere.
For getting the hang of magnifications a good practice object would be the Moon, if it ever stops raining
the effects of changing one eyepiece for another will be quite pronounced - the Moon is pretty easy to find, and there are bold surface features you can use as frames of reference.
As for learning the constellations... a planisphere is good for getting the brighter ones, and this should be good for City-based viewing, but also easy to use all year round. Mostly, just get out there with your eyes with some frame of reference (map, smart phone app, etc) and take your time to get familiar, the universe isn't going anywhere. I'd even say no need even for binoculars initially (although I am a big fan of them for wide field viewing) for getting the hang of things as all the major constellations are naked eye visibility, even if some can be a challenge, depending on your location. I'm having to re-learn for the most part having moved from England this year, so the few that are familiar are upside down
and then there's all the southern constellations I'd not laid eyes on before! All pretty amazing stuff
