Leave it alone. Don't cut anything back. If it will survive, it does not want to be reduced. It might be stored energy, or it might be coming good. Either way, let it do its own thing.
Let it grow for at least a year or 2 mate.
Rory I style Bonsai naturally, just as they would appear in the wild.
Central Coast, NSW
Bonsai: Casuarina Leptospermum Banksia Phebalium Baeckea Melalueca Ficus
Rory makes a valid point. I also agree with your assertion that many natural Eucs feature dead wood so leave excess branches to see if they fit in with the eventual theme. Not too hard to remove it in future but a little bit harder to add dead wood if you decide you need it.
I have dug a couple more trees lately and will start some threads soon, the new hospital they are building is proving to be quite handy, they are even widening the road and all!
Sorry for your loss MacGuyver.
Maybe putting the pots a tray of water may increase your success rate. Whenever I do a re-pot on any of my natives I leave then in a tray of water until they fully recover with great results