Tips for updating/appending armature faster

I have a series of character models I use in various projects across multiple files - and sometimes I will find a way to improve them either on the models themselves or their armatures, etc.

In the case of armature improvements though, I’ve been finding it really tedious and time consuming to then update the same armature in other project files. (appending it to another file, then connecting it to the various models it’s used for)

So I’m really looking for some advice on how to speed this up. Like is there a way to just automatically assign everything dependent on the old model to the newly appended one? Or even just in bigger chunks, like being able to switch all over the shape key driver dependencies over in one operation? (I’ve tried multi-selecting the drivers, but it only seems to update the last one selected) Or maybe somehow update the older versions without having to append the old one at all? Anything along those lines.