One other important point that you may have addressed - but I'm not sure with your routing since it's hard to tell where your stopovers are, so I'll bring it up.

One reason why so few of us book ex-US besides cost (which between hotels and travel over to some nice remote place to pick up tickets and stay a few nights can actually be somewhat similar) is the 2 stopover rule in continent of origin. So...I'm not sure what your plans are with the DCA-DFW-LAX-JFK legs, but one of those three is going to have to be less than 24 hours. Kinda kills the mileage run aspect in North America unless you really wanna kill yourself.

I've always meant to get to TLL some year - had a ridiculous QF fare TLL-SYD a few years back courtesy of this board (think it was like $294) but was too busy to use it so never got to go. Have fun.