I'll try to keep my two cents short and sweet:
Go for it. Hognose are fantastic little snakes. He would make an awesome little addition to your office. If he's already got 10+ meals in him, F/T unscented, he falls into the well-established category. Plus he's already handling well by the sounds of things.
In all seriousness, Dave, I have the utmost respect and admiration for you. I would be willing to bet your animals are some of the best cared for on the forum, or anywhere for that matter. You (with Katie's feelings considered) are the only one who knows your limit. But hognose are really easy (in my experience with Cosmo anyway), take up little space, require tiny meals (very little cost or freezer space) and are just plain cool little snakes unlike any other species I know. And come on, those faces are just too cute!! Don't even get me started on how cute they are when acting "tough" and hooding and hissing, hahahaha!!
I honestly don't feel like adding a hognose will push you over the edge. But I do think it may "scratch the itch".
As long as you and Katie are in agreement, I say go for it!! I think you'll both really enjoy that fun little personality that only a hognose has.