Thanks for all the great feedback
Excellent feedback from everyone. I've got a lot to take into consideration. I do know that I wouldn't be buying a Prorac. If I chose that style, design and build my on with a similar design and extra strength and support. I live in Utah, and spend a lot of time in the mountains and desert. Because of the terrain, I really wanted to avoid mounting on the rear and extending my length any more than it already is (24ft). I can see myself bottoming out a bike rack that extends an extra ~3ft past the bumper. The added height is definitely a valid concern. Both for loading and unloading, as well clearance. Another option I've been tossing around is to fabricate a beefy receiver, mount it solid to the frame and tuck it tight under the bumper. The idea then is to fabricate a mount that would raise the ride height of the rack about 18" above the height of the rear bumper. I'm grateful for all the feedback, keep it coming. Regardless, I'll share pictures of my end product.