Hey Boat Puller....note the front wheel size.....

A serious adventure heavyweight bike with a dirt biased design and he is running a 21" front....Im just sayin.
Hey JTH, I love what you are doing here. I love some "different" ideas and OOTB thinking. I would love to see this bike in person and comb over the details. Just beautiful work and concept.
My best riding buddy is a Harley guy but wants to get into ADV style riding and exploring with me so I sent him this thread to show him he could have BOTH.
I would never want to throw my opinion in on such a great build but if you would like an idea I see may help on this build....stop reading if not
Have you considered or looked at running a sprocket brake on the rear. You may save weight and compress some stuff. I personally have never been a big fan of that huge rear caliper and mount system on Harleys, maybe going to a smaller 4 piston Brembo or similar and then make a bracket to mount it on the drive sprocket like some chopper guys have done could keep braking power or possibly even increase it and cut a couple of pounds of unsprung weight.
Here are a few ideas just to make you think about it a bit...not telling you what to do at all, just thinking outloud and throwing it out there.
http://www.ebay.com/sch/i.html?_nkw=sprocket+brake