Right on, bro!
I had that same trip in mind, but mide got amended by time and a desire to ride more off-road.
You've got a great list going there...lots of things to improve on the basic g/s design. I'd add proper skidplates on the oil pan and centerstand. I'd also leave off the HPN tank. That thing is huge, and after reading about people doing RTW, very few people even NEEDED that size tank. Go for a regular airhead GS tank. It gives you a range of around 200+ depending on terrain.
DR forks...cool idea
Oh yeah...the BEST thing I did for safety on my bike was adding a
LOUD ASS HORN
Stebel air horn really gets people's attention. They think I'm an 18 wheeler. I can guarantee it has saved me from bad situations more than a few times...