you need to choose a season based on prices and weather. i just got back from kenya last week and tickets were $1800 round trip during the peak season. unfortunately the off seasons in kenya are the rainy seasons and travel can be very difficult and sometimes impossible that time of year.
according to
this site:
"Round-trip prices from L.A. to Sydney average around US$1,500 during the peak season (October to February, summer in the southern hemisphere). But if you travel during Australia?s winter and early spring (June through September), you can save as much as US$800."
sounds like the offseason might be the better option in australia.
here are the current
qantas deals, starting at $750 from san fran