Have you considered maybe extend the braces a little further to the left with a second set of vertical holes to allow for the option to center the spare on the tailgate?
I considered making a second set of holes in the carrier I have designed (Not pictured) but not in the aluminum tailgate hinge to center the factory carrier when stacked on top on the tailgate.
Depending on tire size and backspacing you may run into issues with handle access. The distance the hinges will move the tire out may help that.
Thanks, those are the questions and feedback I’m looking for.