will it be possibe to mark on the foto which cutting do you mean so I can see it, I am also thinking to cut off the small branches.Pruning is done to shape the tree. If we don't know what shape you want it to be, we can't help you prune.
I do see a few options for style, but each one would require entirely different cuts. For example if it was my tree I would be thinking a sort of multi-trunk broom style. That would mean cutting off almost everything small, and cutting the thicker branches down by almost half, then letting it grow out a few years.
You could also go with a literati style, and cut off everything except the one branch that's tied down.



Thank you for your idea for these options, much appreciated, by the way I have been to Dandenong years ago.So many options. I could draw hundreds of different pruning options but I'm just wasting time if you don't like 90% of them.
This one removes some of the long, bare branches with no taper. It will take 5 years or more to regrow the branches with better ramification.
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This option leaves most of the branches. Just remove some longer ends. The tree will still have long, bare branches with little taper but might be a passable bonsai in 3 years.
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This option chops way back to remove all the long, bare sections. Improves trunk taper but basically start the tree again. Looking at 10-15 years to develop a good Jm from this hard chop.
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And those are just a few of the options I can find in a 2D photo only seeing the trunk and branch shape from 1 side.
Lucky you?by the way I have been to Dandenong years ago.