I'm going to keep my list Australian.
Favourites
1) Superman - it's the country's best coaster. No contest.
2) Abyss - The best bang for buck coaster style out there.
3) Tower of Terror - The original and the best. When it first opened it was something else. Lap-bars, full speed, full height.
4) Jet Rescue - Out of control, simple, exciting. Who-ever designated is as a family coaster is a crazy man, and I love them.
Bottom of the barrel
1) Motocoaster - Sorry Dreamworld, but it's true. Call it a sign of management at the time, the fact that it could've been a Vekoma Motorbike Coaster and swapped at the last minute for something Intamin somehow turned into a huge mistake. Terrible station design, terrible placement in the park and a bland ride experience. The park would be better off selling it (not hard given the way it was constructed) and turning back into vintage cars. I'm genuinely not one of these overly nostalgic people, change is good, but they destroyed a generational icon in the park and replaced it with something that further ruined another area of the park that was Disney-esque and I really do believe the ride is just so bad that very few guests if any would mourn its loss. Let me put it to you this way, the vintage cars had charm because you could drive it around rides, over bridges, through tunnels etc. all the things the current iteration doesn't have and so if you surveyed guests "would you rather a) Vintage cars back where they were and Mine Ride to open but kill Motocoaster or B ) keep things exactly as they are?" I guarantee most guests would vote the former.