Welcome to FT seasthaday :)

No Delta to Oz. Korean does fly to SYD via ICN.

Only direct flights to Australia are by Qantas (codeshares with AA) and United (also Hawaiin from HNL). Asia is much longer - options are Korean, Cathay, Singapore, etc. Air NZ is from west coast US to NZ and then connecting to Australia; similarly Air Canada from YVR (via HNL). Many options if take the longer route through Europe and Asia.

Thanks for the welcome! I have used miles to upgrade going International before. Is there an option to fly Korean and use miles to upgrade?
Thanks

Delta to Sydney
 

It takes one free ticket or upgrade to get to Seoul and another to go from Seoul to Sydney. Unless you want to spend some time in Korea, that's a very long and very expensive way to get to Sydney. You cannot use AA miles to upgrade on Qantas, but you can get start collecting United miles with their Visa, etc. and then upgrade on United. Look at the United chart to see how many miles it takes on a cheap ticket. It's 15,000 on a B ticket.

I know I sound like a broken record, but here goes: You may want to consider making SYD part of an around-the-world reservation if you really want to stick with SkyTeam/DL miles.

The only way you can go there with miles is by mileage tickets- i don't think you can do any MFUs on this route.
But you'll get a load of miles if you go via ICN (on a paid tkt). :p

fly FLL-LAX nonstop on Song then buy a ticket on Qantas. don't mess around with United.

Wrong. First, there are no SkyTeam upgrade awards, so you can't upgrade on KE using Delta miles. Second, Delta does offer SkyTeam awards from the U.S. to Australia. 100K Coach, 150K Business, and 200K First.

Delta to Sydney
 

While the Delta website shows Australia and New Zealand as award tickets, I think the only way to do this (other than on a round the world ticket) is to fly Korean to Seoul and then down to Sydney (although there have been mentionson this board of the Continental Micronesia flight). And while I like Qantas, the question was about upgrading with miles, and the only way I've found was to fly United and upgrade with United miles. You can't upgrade on Qantas with American miles or on Korean with Delta miles.

That is a SkyTeam award. You should be able to use the Continental Micronesia flights, or any SkyTeam to NRT, then NRT-ICN, then Oz, or other creative routings.

And if you have any of the nearly impossible to use OnePass miles, there is an exception to the NonePass rule here. You can generally get exactly the dates that you want using a SkyTeam award to SYD in any class on KE over ICN in order to get some use out of those generally low value miles (or you could use the more valuable SkyMiles), but the desirable QF trips remain almost completely unobtainoble. Check the posts by platbrownguy to get his complete A, D, J, C, and C+ breakdown on the KE service.

Thank you all so much. I will look into all of your suggestions. I had looked into flying American to get their rewards and trying to use on Quantas, but will keep with Delta and look into my options!

just one warning on Australia flights. if you take the US-SYD nonstop of any kind you'll sleep for 8 hours then wake up with still 6 more hours of flying to go. :p

Don't do it.
 

As much as I hate to say it, SkyTeam to OZ is just plain dumb. Connecting in ICN adds an entire extra day to the itinerary (both flights are overnight). The CO Mike GUM-CNS flight is basically domestic first, and you'd have to connect in at least HNL, GUM, and CNS to get to SYD (assuming you don't get stuck with the island hopper that makes five stops between HNL and GUM), and the CNS-SYD sector would need to be an add-on.

Do as others have suggested. Fly UA or AA/Quantas and suffer through only 14 hours in-flight, not 24 plus a day on the ground (as required by the KE routing). It's actually a bargain reward on UA, and fairly pleasant in C.

I would only connect via ICN if you wanted to see Seoul and could stay a day.

FLL-SYD is roughly 9,300 miles (I recognize no one offers this route non-stop, but I didn't factor in all the connections, for ease of calculation. You'll get the point...). FLL-ICN-SYD is 12,700 - 3,400 miles further. (ICN-SYD is 5,100 miles alone!) This incremental distance is like adding on JFK-LHR to your journey.

I find that many Americans have no idea as to the relative locations of Asian, Australian and Oceanic countries. I had a funny experience while travelling with customers last year. We were in SYD, and were taking a flight to SIN. I wasn't paying attention to what these guys were doing, and they boarded the flight with no carry-ons. They thought it would be a 2 hour flight. "Sydney and Singapore are close, right?" Perhaps they thought it was more like the Boston Shuttle? They had no books, work, or anything with them - they checked all their bags - and had nothing to keep them busy.

These cities are nearly 4,000 miles apart - 8 hours! Singapore is west of the western edge of Australia! Needless to say, they enjoyed looking at the central part of Australia out the window.

When I got home, I bought my 18-month-old son an inflatable globe so we can start early.

15 hours from LAX to SYD. Ugh. It certainly gives you an appreciation of Pacific geography. We made the jouney on AirNZ direct from LAX a few years ago.