With regard to your itinerary, are you aware that LA starts flying LIM-IPC early Jan 2011?
Currently, you are visiting SCL twice (DFW-SCL-IPC-SCL-SYD)
you could change this to ...LIM-IPC-SCL... getting LIM as additional stopover
(side trips to CUZ and/or IQT and/or GPS?)
Since there are no OW flights DFW-LIM, you'd have to make a change there too; I suggest YVR-JFK-LIM-IPC-SCL-SYD...
CX for YVR-JFK
LA or the AA codeshare for JFK-LIM
AA codeshare probably - so that you have at least one AA (marketed) segment for when you book through the AA RTW desk!
unless you realy want to go to DFW...
or can't stand the big apple...
or find LIM so passe...