IMO, I wouldn't mount the rear tire towards the right like in your pictures AJ. When you turn your head to back up, you look over your right shoulder and the tire would be in your way. To see around it, you'd have to crank your head more around like an owl.
Example of this: You've seen the back hatch of an Xterra. Notice the hatch and hatch window dip on the passenger's side. That's for better visibility when in reverse.
I like Matt's idea and have too thought about this. But I'd have the tire seated more to the drivers side. I also like the idea of making sliders attach to the tire carrier and bracing it to the steel underneath the step pad on the back bumper.