10 days isn't much time! If you're flying across time zones, you'll have a day or two of flying time, plus a day or two of jet lag recovery time.
We flew from Japan into London, and it took me a couple days before I felt up to doing something. However, maybe jet lag doesn't affect you so much.
[HR][/HR]
As far as suggestions go ...
-- Japan ... especially Hokkaido.
-- Australia ... August is winter, but toward the end of winter. Queensland would be nice and warm ... the Perth area might be nice then too. Victoria would be a little cooler, but not bad along the Great Ocean Road. There wouldn't be many tourists around then.
-- Canadian Rockies ... have you done the Icefield Parkway and surrounding area? Late August is a nice time to go there.
-- Europe ... Europe is big, and 10 days is very short. If I had to recommend somewhere there, I might recommend getting into the Martigny area of Switzerland and following the Rhone Route. It's in the Alps without all the effort, and yet would be quite spectacular. On one day, take the train to Chamonix France and ride the gondola up to the viewpoint for Mont Blanc. That would definitely be memorable!!