Before last week I would of told you to keep the flight you had and try to get the 7a flight out of SEA. The reason for this is because DL was suppose to fly this route with BE up front. For some reason they changed their mind and now just the really bad 757-200 config.
I am on this route for Aug. I called SMS yesterday and I told the agent the situation. She immediately was like "How could DL do that to you? That is nowhere near enough time to get through SEA with your luggage." She pretty much told me I had free choice of how I wanted to return. It may of been the nicest agent i have ever spoken to at SMS. Ask for Cassity!!!!
DL 16 (77L) is flying from LAX that day (checked for you.). I would suggest taking DL 1212 from OGG-LAX and then DL 16 from LAX-ATL. On this flight from LAX you will have the flat seats. Plus you get to leave OGG 2 hours later (10p now).
I guess the only problem is that you may have some grumpy passengers who had to leave SYD. I guess we would be the same for having to leave OGG.