Any type of auto tagging feature would be achievable if provided with the right triggers on IFTTT. Detecting which notebook or area the note is added to. Even getting the entire hierarchy as a variable is possible in IFTTT. Auto adding tags as the output is possible if the devs added support for it. I guess I didn't read the OP as in depth, but basically I was looking for auto tagging based on note title matching.
This feature can be so easily achieved. Just create hook into IFTTT and allow the user to configure tag rules based on detected input triggers.