Well the Load and breakdown apps seem rather barebones, and come with the major caveat that you must initiate this update through some mechanism in a running maya session, whether that’s via script at best or far worse through manual efforts, I see it as a very likely point of failure and ultimately unnecessary.
We have been using a nested referencing workflow for many years, where a geo is ref’d into a rig, rig into a lookdev, rig into an anim, anim into a lighting scene (lookdev materials also into the lighting), etc…
Over that time the number of times this workflow has bitten us is so little and never truly dramatic, that I can’t even imagine how many hours it’s saved in not needing to update some downstream reference. Far more likely is that the user forgets to update a versioned ref to the latest, (like what just happened at a friends studio using ftrack, leading to all kinds of chaos and delays between departments simply due to a camera ref being out of date).
I’ve started replicating our existing publish system yesterday in shotgun, and it’s got it’s basic functionality already in place 
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Our existing custom pipeline didn’t even have a backup / versioning of these published items, since to recreate them you just rerun the publish function from the working file, (sounds dangerous I know, but hasn’t been an issue).
Moving forward however I do plan on keeping versioned published backups, and implementing a symlink to the versionless file like NIM uses. I’m also hoping to leverage shotgun to keep notes on the history of that versionless file so rollback, relinking, and hardcoding to another version is possible, and all scenes using it downstream will be up to date without any further user intervention.